BACKGROUND There are no studies on incidental anal ^18F-fluorodeoxyglucose(^18FDG)uptake.AIM To assess the rate and aetiologies of incidental anal ^18FDG uptake and to evaluate the correlation between ^18FDG positron-...BACKGROUND There are no studies on incidental anal ^18F-fluorodeoxyglucose(^18FDG)uptake.AIM To assess the rate and aetiologies of incidental anal ^18FDG uptake and to evaluate the correlation between ^18FDG positron-emission tomography/computed tomography(PET/CT)parameters and the diagnosis of an anorectal disease.METHODS The data from patients with incidental anal ^18FDG uptake were retrospectively analysed.Patients who underwent anorectal examinations were identified and compared to those who did not undergo examinations.Patients who were offered treatment were then identified and compared to those who did not receive treatment.RESULTS Among the 43020^18FDG PET/CT scans performed,197^18FDG PET/CT scans of 146 patients(0.45%)reported incidental anal uptake.Among the 134 patients included,48(35.8%)patients underwent anorectal examinations,and anorectal diseases were diagnosed in 33(69.0%)of these patients and treated in ^18/48(37.5%)patients.Among the examined patients,those with a pathology requiring treatment had significantly smaller metabolic volumes(MV)30 and MV41 values and higher maximal and mean standardized uptake value measurements than those who did not require treatment.CONCLUSION Incidental anal ^18FDG uptake is rare,but a reliable anorectal diagnosis is commonly obtained when an anorectal examination is performed.The diagnosis of an anorectal disease induces treatment in more than one-third of the patients.These data should encourage practitioners to explore incidental anal ^18FDG uptake systematically.展开更多
Positron emission tomography(PET)with F‐18 fluorodeoxyglucose(FDG)is an established tool in clinical molecular imaging for evaluating metabolic activity.Advanced PET systems enable high‐resolution three‐dimensional...Positron emission tomography(PET)with F‐18 fluorodeoxyglucose(FDG)is an established tool in clinical molecular imaging for evaluating metabolic activity.Advanced PET systems enable high‐resolution three‐dimensional analysis of FDG distribution,offering insightful information for lesion characterization.Furthermore,dynamic whole‐body imaging facilitates assessment of temporal FDG uptake following its administration.This development introduces the concept of four‐dimensional(4D)FDG PET/CT,enhancing the precision of lesion characterization.A critical advantage of applying 4D FDG PET/CT is the ability to distinguish pathological from physiological FDG uptake by analyzing motion‐related uptake.Correcting motion and integrating serial imaging data enable accurate interpretation.Additionally,FDG uptake quantification is possible using Patlak analysis.This review discusses innovative clinical applications and quantitative techniques for analyzing FDG distribution through 4D FDG PET/CT.展开更多
BACKGROUND Malignant pleural mesothelioma(MPM),a rare aggressive malignancy,is primarily caused by asbestos exposure.MPM typically affects older adults(median age,76 years),is uncommon in those under age 50 years and ...BACKGROUND Malignant pleural mesothelioma(MPM),a rare aggressive malignancy,is primarily caused by asbestos exposure.MPM typically affects older adults(median age,76 years),is uncommon in those under age 50 years and shows male predominance.Based on the American Society of Clinical Oncology guidelines,F-18 fluorodeoxyglucose positron emission tomography/computed tomography(F-18 FDG PET/CT)is essential for initial MPM staging.Integrating quantitative FDG metabolic data with computed tomography(CT)anatomy optimizes biopsy accuracy and staging.CASE SUMMARY A 21-year-old female college student presented with fever(peak 38.4°C),cough,and white mucoid sputum after cold exposure.Initial evaluation revealed elevated C-reactive protein[C-reactive protein(CRP);65.52 mg/L]and Mycoplasma pneumoniae IgM.Despite resolution of fever following a 14-day moxifloxacin regimen,persistent cough prompted chest CT,which demonstrated left pleural mass-like thickenings.Levofloxacin therapy for 2 weeks failed to alleviate symptoms,accompanied by 2.5-kg weight loss over 1 month.Re-evaluation showed rising CRP(88.87 mg/L)with stable CT lesions,and negative T-cell spot test for tuberculosis and tumor markers.Contrast-enhanced CT revealed heterogeneously enhancing masses,while PET/CT detected two broad-based pleural lesions with intense FDG avidity.CT-guided biopsy confirmed epithelioid MPM.Thoracoscopy exposed diffuse fragile,hemorrhagic nodules implanting on diaphragmatic and parietal pleura,confirming metastatic MPM with partial resection performed.This presentation challenges conventional imaging paradigms of MPM,underscoring its diagnostic complexity.CONCLUSION MPM should still be considered an important differential diagnosis in young patients presenting with solitary pleural masses and no history of typical asbestos exposure.F-18 FDG PET/CT,while serving as an essential component of initial staging for MPM,has some inherent limitations.展开更多
Ovarian cancer(OC)is the most lethal gynecological malignancy.Diagnosis usually occurs late,and even with the most effective treatment relapses are frequent.Early diagnosis and precise staging are critical for achievi...Ovarian cancer(OC)is the most lethal gynecological malignancy.Diagnosis usually occurs late,and even with the most effective treatment relapses are frequent.Early diagnosis and precise staging are critical for achieving better treatment outcomes and prognoses.Conventional imaging methods such as ultrasound(US),computed tomography(CT),and magnetic resonance imaging(MRI)are the main imaging techniques supporting management decisions.However,advancements in molecular imaging have made positron emission tomography/computed tomography(PET/CT)a promising noninvasive imaging option for better management of OC.The literature provides evidence indicating that fluorine‐18‐fluorodeoxyglucose(^(18)F‐FDG)PET/CT(FDG‐PET/CT)is effective in primary tumor diagnosis,staging,prognosis evaluation,treatment response assessment,and relapse surveillance.Looking ahead,significant attention should be paid to tracers beyond FDG,integrated PET/MRI,dynamic PET,and artificial intelligence(AI)‐based radiomics.This review examines the application of PET/CT in OC management at each disease stage and discusses its future potential.展开更多
A 16‐year‐old male teenager with no prior medical history suddenly experienced right upper limb weakness.The weakness persisted for 2 weeks,followed by a headache and unstable walking.On physical examination,the pat...A 16‐year‐old male teenager with no prior medical history suddenly experienced right upper limb weakness.The weakness persisted for 2 weeks,followed by a headache and unstable walking.On physical examination,the patient exhibited decreased verbal fluency,a shallow right nasolabial fold,and tongue movement to the right side.Reduced muscle strength with normal muscle tension was observed in the right limb.On laboratory examination,lymphocytes were decreased,and neutrophils were slightly increased.The patient underwent brain CT,MRI,and whole‐body ^(18)F‐fluorodeoxyglucose PET/CT.Intra-cranial biopsy was performed to confirm the pathology(Figure 1).The final pathological diagnosis was the Rosai-Dorfman disease,characterized by abnormal hyperplasia of the sinuses combined with an accumulation of histiocytes in the lymph nodes.Although extranodal involvement has been reported,primary infiltration of the central nervous system is extremely rare,particularly in the brain parenchyma.展开更多
AIM： To investigate the correlations of pre-treatmentpositron emission tomography-computer tomography（PET-CT） metabolic quantifiers with clinical data ofunstratified gastric cancer （GC） patients.METHODS： Forty P...AIM： To investigate the correlations of pre-treatmentpositron emission tomography-computer tomography（PET-CT） metabolic quantifiers with clinical data ofunstratified gastric cancer （GC） patients.METHODS： Forty PET-CT scans utilising 18-fluorodeoxyglucosein patients who received no prior treatmentwere analysed. Analysis involved measurements ofmaximum and mean standardised uptake volumes（SUV）, coefficient of variation （COV）, metabolictumour volumes and total lesion glycolysis of differentthresholds above which the tumor volumes wereidentified. The threshold values were： SUV absolutevalue of 2.5, 30% of SUVmax, 40% of SUVmax,and liver uptake-based （marked 2.5, 30, 40 and liv,respectively）. Clinical variables such as age, sex,clinical stage, performance index, weight loss, tumorhistological type and grade, and CEA and CA19.9 levelswere included in survival analysis. Patients receivedvarious treatment modalities appropriate to theirdisease stage and the outcome was defined by time tometastasis （TTM） and overall survival （OS）. Clinical andmetabolic parameters were evaluated by analysis of variance, receiver operating characteristics, univariateKaplan-Meier, and multivariate Cox models. P 〈 0.05was considered statistically significant.RESULTS： Significant differences were observedbetween initially disseminated and non-disseminatedpatients in mean SUV （6.05 vs 4.13, P = 0.008）, TLG2.5（802 cm3 vs 226 cm3; P = 0.031）, and TLG30 （436 cm3vs 247 cm3, P = 0.018）. Higher COV was associatedwith poor tumour differentiation （0.47 for G3 vs0.28 for G1 and G2; P = 0.03）. MTV2.5 was positivelycorrelated to patient weight loss （〈 5%, 5%-10%and 〉 10%： 40.4 cm3 vs 123.6 cm3 vs 181.8 cm3,respectively, P = 0.003）. In multivariate Cox analysis,TLG30 was prognostic for OS （HR = 1.001, 95%CI：1.0009-1.0017; P = 0.047） for the whole group ofpatients. In the same model yet only including patientswithout initial disease dissemination TLG30 （HR = 1.009,95%CI： 1.003-1.014; P = 0.004） and MTV2.5 （HR = 1.02,95%CI： 1.002-1.036; P = 0.025） were prognostic forOS; for TTM TLG30 was the only significant prognosticvariable （HR = 1.006, 95%CI： 1.001-1.012; P = 0.02）.CONCLUSION： PET-CT in GC may represent a valuablediagnostic and prognostic tool that requires furtherevaluation in highly standardised environments such asrandomised clinical trials.展开更多
AIM To evaluate the value of pre-treatment 18F-FDG PET/CT in patients with HCC following liver radioembolization.METHODS We identified 34 patients with HCC who underwent an FDG PET/CT scan prior to hepatic radioemboli...AIM To evaluate the value of pre-treatment 18F-FDG PET/CT in patients with HCC following liver radioembolization.METHODS We identified 34 patients with HCC who underwent an FDG PET/CT scan prior to hepatic radioembolization at our institution between 2009 and 2013. Patients wereseen in clinic one month after radioembolization and then at 2-3 mo intervals. We assessed the influence of FDG tumor uptake on outcomes including local liver control(LLC), distant liver control(DLC), time to distant metastases(DM), progression free survival(PFS) and overall survival(OS).RESULTS The majority of patients were males(n = 25, 74%), and had Child Pugh Class A(n = 31, 91%), with a median age of 68 years(46-84 years). FDG-avid disease was found in 19(56%) patients with SUVmax ranging from 3 to 20. Female patients were more likely to have an FDG-avid HCC(P = 0.02). Median follow up of patients following radioembolization was 12 months(1.2-62.8 mo). FDG-avid disease was associated with a decreased 1 year LLC, DLC, DM and PFS(P < 0.05). Using multivariate analysis, FDG avidity predicted for LLC, DLC, and PFS(all P < 0.05).CONCLUSION In this retrospective study, pre-treatment HCC FDGavidity was found to be associated with worse LLC, DLC, and PFS following radioembolization. Larger studies are needed to validate our initial findings to assess the role of F-18-FDG PET/CT scans as biomarker for patients with HCC following radioembolization.展开更多
Recently, several reports have demonstrated that fluorine-18 fluorodeoxyglucose positron emission tomography （FDG-PET） is useful in differentiating between benign and malignant lesions in the gallbladder. However, t...Recently, several reports have demonstrated that fluorine-18 fluorodeoxyglucose positron emission tomography （FDG-PET） is useful in differentiating between benign and malignant lesions in the gallbladder. However, there is a limitation in the ability of FDG-PET to differentiate between inflammatory and malignant lesions. We herein present a case of xanthogranulomatous cholecystitis misdiagnosed as gallbladder carcinoma by ultrasonography and computed tomography. FDG-PET also showed increased activity. In this case, FDG-PET findings resulted in a false-positive for the diagnosis of gallbladder carcinoma.展开更多
AIM To determine the relationship between F-18 fluorodeoxyglucose(FDG) uptake of bone marrow(BM) on positron emission tomography/computed tomography(PET/CT) and clinical factors and to assess the prognostic value of F...AIM To determine the relationship between F-18 fluorodeoxyglucose(FDG) uptake of bone marrow(BM) on positron emission tomography/computed tomography(PET/CT) and clinical factors and to assess the prognostic value of FDG uptake of BM in gastric carcinoma.METHODS We retrospectively enrolled 309 gastric cancer patients who underwent staging FDG PET/CT and curative surgical resection. FDG uptake of primary tumor was visually classified as positive or negative FDG uptake. Mean FDG uptake of BM(BM SUV) and BM-to-liver uptake ratio(BLR) were measured. The relationships of BM SUV or BLR with clinical factors were evaluated. The prognostic values of BM SUV, BLR, and other clinical factors for predicting recurrence-free survival(RFS) and overall survival(OS) were assessed.RESULTS Of 309 patients, 38 patients(12.3%) experienced cancer recurrence and 18 patients(5.8%) died. Patients with advanced gastric cancer, positive FDG uptake, and recurrence had higher values of BM SUV and BLR than those with early gastric cancer, negative FDG uptake, and no recurrence(P < 0.05). BM SUV and BLR were significantly correlated with hemoglobin level, neutrophil-to-lymphocyte ratio, and platelet-tolymphocyte ratio(P < 0.05). On multivariate analysis, multiple tumors, T stage, lymph node metastasis, tumor involvement of resection margin, and BLR were significantly associated with RFS(P < 0.05). T stage, lymph node metastasis, hemoglobin level, and BLR were significantly associated with OS(P < 0.05). CONCLUSION BLR on PET/CT was an independent prognostic factor for RFS and OS in gastric cancer patients with curative surgical resection.展开更多
AIM: To evaluate the influence of baseline maximum standardized uptake value(SUVmax) on survival in a cohort of patients, undergoing positron emission tomography-computed tomography(PET-CT) scan for esophageal carcino...AIM: To evaluate the influence of baseline maximum standardized uptake value(SUVmax) on survival in a cohort of patients, undergoing positron emission tomography-computed tomography(PET-CT) scan for esophageal carcinoma. METHODS: The pre-treatment SUVmax numeric reading was determined in patients with confirmed esophageal or junctional cancer having PET-CT scan during the time period 1st January 2007 until 31 st July 2012. A minimum follow up of 12 mo was required. Patients were subdivided into quartiles according to SUVmax value and the influence of SUVmax on survival was assessed using univariate and multivariate analysis. The following pre-treatment factors were investigated: patient characteristics, tumor characteristics and planned treatment. RESULTS: The study population was 271 patients(191male) with esophageal or junctional carcinoma. The median age was 65 years(range 40-85) and histologic subtype was adenocarcinoma in 197 patients and squamous carcinoma in 74 patients. The treatment intent was radical in 182 and palliative in 89 patients. SUVmax was linked to histologic subtype(P = 0.008), tumor site(P = 0.01) and Union for International Cancer Control(UICC) stage(P < 0.001). On univariate analysis, prognosis was significantly associated with SUVmax(P = 0.001), T-stage(P < 0.001) and UICC stage(P < 0.001). On multivariate analysis, only T-stage and UICC stage remained significant. CONCLUSION: Pretreatment SUVmax was not a useful marker in isolation for determining prognosis of patients with esophageal carcinoma.展开更多
BACKGROUND Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography(F-18 FDG PET/CT),a functional imaging method,is usually performed on the entire torso,and regions of unexpected suspicious foc...BACKGROUND Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography(F-18 FDG PET/CT),a functional imaging method,is usually performed on the entire torso,and regions of unexpected suspicious focal hypermetabolism are not infrequently observed.Among the regions,colon,thyroid,and prostate were found to be the common organs in a recent umbrella review.Some studies reported that a high rate of malignancy was shown in incidentally identified focal hypermetabolic regions and suggested that further examinations should not be ignored.AIM To investigate the malignancy rate of incidental focal FDG uptake,useful PET parameters and their cutoffs in discrimination between malignant and benign lesions.METHODS Retrospectively,the final reports of 16510 F-18 FDG PET/CT scans performed at our hospital between January 2016 and March 2022 were reviewed to identify incidentally observed FDG uptake in the colon/rectum,thyroid,and prostate.The scans of patients with current or prior malignancies at each corresponding location,without the final reports of histopathology or colonoscopy(for colon and rectum)for the corresponding hypermetabolic regions,or with diffuse(not focal)hypermetabolism were excluded.Finally,88 regions of focal colorectal hypermetabolism in 85 patients(48 men and 37 women with mean age 67.0±13.4 years and 63.4±15.8 years,respectively),48 focal thyroid uptakes in 48 patients(12 men and 36 women with mean age 62.2±13.1 years and 60.8±12.4 years,respectively),and 39 focal prostate uptakes in 39 patients(mean age 71.8±7.5 years)were eligible for this study.For those unexpected focal hypermetabolic regions,rates of malignancy were calculated,PET parameters,such as standardized uptake value(SUV),capable of distinguishing between malignant and benign lesions were investigated,and the cutoffs of those PET parameters were determined by plotting receiver operating characteristic curves.RESULTS In the colon and rectum,29.5%(26/88)were malignant and 33.0%(29/88)were premalignant lesions.Both SUVmax and SUVpeak differentiated malignant/premalignant from benign lesions,however,no parameters could distinguish malignant from premalignant lesions.Higher area under the curve was shown with SUVmax(0.752,95%CI:0.649-0.856,P<0.001)and the cutoff was 7.6.In the thyroid,60.4%(29/48)were malignant.The majority were well-differentiated thyroid cancers(89.7%,26/29).The results of BRAF mutation tests were available for 20 of the 26 welldifferentiated thyroid cancers and all 20 had the mutation.Solely SUVmax differentiated malignant from benign lesions and the cutoff was 6.9.In the prostate,56.4%(22/39)were malignant.Only SUVmax differentiated malignant from benign lesions and the cutoff was 3.8.Overall,among the 175 focal hypermetabolic regions,60.6%(106/175)were proven to be malignant and premalignant(in colon and rectum)lesions.CONCLUSION Approximately 60%of the incidentally observed focal F-18 FDG uptake in the colon/rectum,thyroid,and prostate were found to be malignant.Of the several PET parameters,SUVmax was superior to others in distinguishing between malignant/premalignant and benign lesions.Based on these findings,incidental focal hypermetabolism should not be ignored and lead physicians to conduct further investigations with greater confidence.展开更多
AIM To determine the significance and need for investigation of incidental prostatic uptake in men undergoing ^(18)F-labelled fluorodeoxyglucose(^(18)F-FDG) positron emission tomography/computed tomography(PET/CT) for...AIM To determine the significance and need for investigation of incidental prostatic uptake in men undergoing ^(18)F-labelled fluorodeoxyglucose(^(18)F-FDG) positron emission tomography/computed tomography(PET/CT) for other indications.METHODS Hospital databases were searched over a 5-year period for patients undergoing both PET/CT and prostate magnetic resonance imaging(MRI). For the initial analysis, the prostate was divided into six sectors and suspicious or malignant sectors were identified using MRI and histopathology reports respectively. Maximum and mean ^(18)F-FDG standardised uptake values were measured in each sector by an investigator blinded to the MRI and histopathology findings. Two agematched controls were selected per case. Results were analysed using a paired t-test and one-way ANOVA. For the second analysis, PET/CT reports were searched for prostatic uptake reported incidentally and these patients were followed up. RESULTS Over a 5-year period, 15 patients underwent both PET/CT and MRI and had biopsy-proven prostate cancer.Malignant prostatic sectors had a trend to higher ^(18)F-FDG uptake than benign sectors, however this was neither clinically nor statistically significant(3.13 ±0.58 vs 2.86 ± 0.68, P > 0.05). ^(18)F-FDG uptake showed no correlation with the presence or histopathological grade of tumour. ^(18)F-FDG uptake in cases with prostate cancer was comparable to that from age-matched controls. Forty-six(1.6%) of 2846 PET/CTs over a 5-year period reported incidental prostatic uptake. Of these, 18(0.6%) were investigated by PSA, 9(0.3%)were referred to urology, with 3(0.1%) undergoing MRI and/or biopsy. No cases of prostate cancer were diagnosed in patients with incidental ^(18)F-FDG uptake in our institute over a 5-year period.CONCLUSION ^(18)F-FDG uptake overlaps significantly between malignant and benign prostatic conditions. Subsequent patient management was not affected by the reporting of incidental focal prostatic uptake in this cohort.展开更多
AIMTo noninvasively investigate tumor cellularity measured using diffusion-weighted magnetic resonance imaging(DW-MRI)and glucose metabolism measured by<sup>18</sup>F-labeled fluorodeoxyglucose positron em...AIMTo noninvasively investigate tumor cellularity measured using diffusion-weighted magnetic resonance imaging(DW-MRI)and glucose metabolism measured by<sup>18</sup>F-labeled fluorodeoxyglucose positron emission tomography/computed tomography(<sup>18</sup>F-FDG-PET/CT)during radiation therapy(RT)for human papillomavirus negative(HPV-)head and neck squamous cell carcinoma(HNSCC).METHODSIn this prospective study,6 HPV-HNSCC patients underwent a total of 34 multimodality imaging examinations DW-MRI at 1.5 T Philips MRI scanner[(n=24)pre-,during-(2-3 wk),and post-treatment(Tx),and<sup>18</sup>F-FDG PET/CT pre-and post-Tx(n=10)].All patients received RT.Monoexponential modeling of the DW-MRI data yielded the imaging metric apparent diffusion coefficient(ADC)and the mean of standardized uptake value(SUV)was measured from<sup>18</sup>F-FDG PET uptake.All patients had a clinical follow-up as the standard of care and survival status was documented at 1 year.RESULTSThere was a strong negative correlation between the mean of pretreatment ADC(ρ=-0.67,P=0.01)and the pretreatment<sup>18</sup>F-FDG PET SUV.The percentage(%)change in delta(∆)ADC for primary tumors and neck nodal metastases between pre-and Wk<sub>2-3</sub>Tx were as follows:75.4%and 61.6%,respectively,for the patient with no evidence of disease,27.5%and 32.7%,respectively,for those patients who were alive with disease,and 26.9%and 7.31%,respectively,for those who were dead with disease.CONCLUSIONThese results are preliminary in nature and are indicative,and not definitive,trends rendered by the imaging metrics due to the small sample size of HPV-HNSCC patients in a Meixoeiro Hospital of Vigo Experience.展开更多
BACKGROUND Colon and rectal cancers are among the top five cancers worldwide in terms of their incidence and mortality rates.As the treatment options for cure include surgery even in specific advanced-stage cases,the ...BACKGROUND Colon and rectal cancers are among the top five cancers worldwide in terms of their incidence and mortality rates.As the treatment options for cure include surgery even in specific advanced-stage cases,the early detection of lesions is important for applying active treatment methods.Fluorine-18 fluorodeoxyglucose(F-18 FDG)positron emission tomography/computed tomography(PET/CT)is an established imaging study for many types of cancers;however,physiologic uptake in the gastrointestinal tract is a frequent finding and may interfere with lesion identification.Nevertheless,as unexpectedly observed focal colorectal F-18 FDG uptake may harbor malignant lesions,further examination must not be avoided.AIM To assess the clinical implications of unexpected focal colorectal F-18 FDG uptake by analyzing FDG PET parameters.METHODS A total of 15143 F-18 FDG PET/CT scans performed at our hospital between January 2016 and September 2021 were retrospectively reviewed to identify incidentally observed focal colorectal FDG uptake.Finally,83 regions showing focal colorectal FDG uptake with final histopathological reports from 80 patients(45 men and 35 women with mean ages of 66.9±10.7 years and 63.7±15.3 years,respectively)were eligible for inclusion in the present study.Each focal hypermetabolic colorectal region was classified as malignant,premalignant,or benign according to the histopathological report.PET parameters such as maximum and peak standardized uptake value(SUVmax and SUVpeak),metabolic tumor volume(MTV),mean SUV of the metabolic tumor volume(mSUVmtv),and total lesion glycolysis(TLG)were measured or calculated for the corresponding hypermetabolic regions.Parametric and nonparametric statistical comparisons of these parameters were performed among the three groups.Receiver operating characteristic curves were plotted to identify cut-off values.RESULTS The detection rate of incidental focal colorectal uptake was 0.53%(80/15,143).Of the 83 regions with unexpected focal colorectal hypermetabolism,28.9%(24/83)were malignant,32.5%(27/83)were premalignant,and 38.6%(32/83)were benign.Overall,61.4% of the regions had malignant or premalignant lesions.SUVmax,SUVpeak,and mSUVmtv differentiated malignant and/or premalignant lesions from benign lesions with statistical significance(P<0.05).mSUVmtv3.5 differentiated malignant from benign lesions,with the largest area under the curve(AUC)of 0.792 and a cut-off of 4.9.SUVmax showed the largest AUC of 0.758 with a cut-off value of 7.5 for distinguishing between premalignant and benign lesions.Overall,SUVmax with a cut-off value of 7.6(AUC:0.770,95% confidence interval(CI):0.668-0.872;sensitivity,0.686;specificity,0.688)was a superior parameter for distinguishing between malignant/premalignant and benign lesions or physiologic uptake.No parameters differentiated malignant from premalignant lesions.Moderate or weak positive correlations were observed between the long diameter of the malignant lesions and PET parameters such as SUVpeak and some mSUVmtv.CONCLUSION Approximately two-thirds(61.4%)of incidental focal hypermetabolic colorectal regions were malignant/premalignant lesions,for which SUVmax was an independent diagnostic parameter.Unexpected suspicious focal colorectal FDG uptake should not be avoided and consideration for further evaluation is strongly recommended not to miss the two-thirds.展开更多
BACKGROUND Lymphangioma is a rare benign cystic tumor believed to be a proliferation of heterotopic lymphocytes.It is caused by congenital lymphatic dysplasia or other acquired factors related to surgery,trauma,infect...BACKGROUND Lymphangioma is a rare benign cystic tumor believed to be a proliferation of heterotopic lymphocytes.It is caused by congenital lymphatic dysplasia or other acquired factors related to surgery,trauma,infection,or cancer.In this article,we present the case of an adult patient who underwent multi-modal imaging and whose condition was finally confirmed to be multiple cystic lymphangiomas by pathological examination.CASE SUMMARY A 61-year-old man was referred to our hospital for having suffered from painless gross hematuria for 2 wk.Multiple masses rising from the retroperitoneum and pelvis were found incidentally by urinary ultrasonography.Contrast-enhanced abdominal-pelvic computed tomography showed multiple well-defined hypodense cystic lesions without enhancement.The lesions showed no uptake on F-18-fluorodeoxyglucose positron emission tomography/computed tomography images.Exploratory laparotomy was performed,and the case was confirmed as multiple cystic lymphangiomas.CONCLUSION When retroperitoneal and pelvic masses are found,clinicians should always consider cystic lymphangioma when making a differential diagnosis.展开更多
BACKGROUND Diagnosis of prosthetic vascular graft infection with[(18)F]fluorodeoxyglucose positron emission tomography/computed tomography(18F-FDG PET/CT)allows for early detection of functional changes associated wit...BACKGROUND Diagnosis of prosthetic vascular graft infection with[(18)F]fluorodeoxyglucose positron emission tomography/computed tomography(18F-FDG PET/CT)allows for early detection of functional changes associated with infection,based on increased glucose utilization by activated macrophages and granulocytes.Aseptic vascular grafts,like all foreign bodies,can stimulate an inflammatory response,which can present as increased activity on 18F-FDG PET/CT.Consequently,distinguishing aseptic inflammation from graft infection,though important,can be difficult.In the case of endovascular aneurysm repair(EVAR),a minimally invasive procedure involving the transfemoral insertion of an endoprosthetic stent graft,the normal postoperative appearance of these grafts on 18F-FDG PET/CT can vary over time,potentially confounding study interpretation.AIM To investigate the visual,semiquantitative,and temporal characteristics of aseptic vascular grafts in patients status post EVAR.METHODS In this observational retrospective cohort study,patients with history of EVAR who underwent 18F-FDG PET/CT for indications other than infection were identified retrospectively.All patients were asymptomatic for graft infection-no abdominal pain,fever of unknown origin,sepsis,or leukocytosis-at the time of imaging and for≥2 mo after each PET/CT.Imaging studies such as CT for each patient were also reviewed,and any patients with suspected or confirmed vascular graft infection were excluded.One hundred two scans performed on 43 patients(34 males;9 females;age=77±8 years at the time of the final PET/CT)were retrospectively reviewed.All 43 patients had an abdominal aortic(AA)vascular graft,40 patients had a right iliac(RI)limb graft,and 41 patients had a left iliac(LI)limb graft.Twentytwo patients had 1 PET/CT and 21 patients had from 2 to 9 PET/CTs.Grafts were imaged between 2 mo to 168 mo(about 14 years)post placement.Eight grafts were imaged within 6 mo of placement,including three that were imaged within three months of placement.The mean interval between graft placement and PET/CT for all 102 scans was 51±39 mo.PET/CT data was reconstructed with region-of-interest analysis of proximal,mid and distal portions of the grafts and background ascending aorta.Maximum standardized uptake value(SUVmax)was recorded for each region.SUVmax-to-background uptake ratios(URs)were calculated.Visual assessment was performed using a 2-pattern grading scale:Diffuse(homogeneous uptake less than liver uptake)and focal(one or more areas of focal uptake in any part of the graft).Statistical analysis was performed.RESULTS In total,there were 306 AA grafts,285 LI grafts,282 RI grafts,and 306 ascending aorta background SUVmax measurements.For all 102 scans,mean SUVmax values for AA grafts were 2.8-3.0 along proximal,mid,and distal segments.Mean SUVmax values for LI grafts and RI grafts were 2.7-2.8.Mean SUVmax values for background were 2.5±0.5.Mean URs were 1.1-1.2.Visual analysis of the scans reflected results of quantitative analysis.On visual inspection,98%revealed diffuse,homogeneous 18F-FDG uptake less than liver.Graft URs and visual pattern categories were significantly associated for AA graft URs(F-ratio=21.5,P<0.001),LI graft URs(F-ratio=20.4,P<0.001),and RI graft URs(F-ratio=30.4,P<0.001).Thus,visual patterns of 18F-FDG uptake corresponded statistically significantly to semiquantitative URs.The age of grafts showing focal patterns was greater than grafts showing diffuse patterns,87±89 vs 50±37 mo,respectively(P=0.02).URs were significantly associated with graft age for AA grafts(r=0.19,P=0.001).URs were also significantly associated with graft age for LI grafts(r=0.25,P<0.0001),and RI grafts(r=0.31,P<0.001).Quartiles of similar numbers of graft(n=25-27)grouped by graft age indicated that URs were significantly higher for 4th quartile vs 2nd quartile URs(F-ratio=19.5,P<0.001).When evaluating URs,graft SUVmax values within 10%-20%of the ascending aorta SUVmax is evident in aseptic grafts,except for grafts in the oldest quartiles.In this study,grafts in the oldest quartiles(>7 years post EVAR)showed SUVmax up to 30%higher than the ascending aorta SUVmax.CONCLUSION Characteristics of an aseptic vascular stent graft in the aorta and iliac vessels on 18F-FDG PET/CT include graft SUVmax values within 10%-20%of the ascending aorta background SUVmax.The SUVmax of older aseptic grafts can be as much as 30%above background.The visual uptake pattern of diffuse,homogeneous uptake less than liver was seen in 98%of aseptic vascular grafts,making this pattern particularly reassuring for clinicians.展开更多
Synovial sarcoma is a relatively rare subset of soft tissue sarcoma.A male patient with an anterior mediastinal mass and multiple pulmonary nodules underwent 18F-FDG and 68Ga-(1,4,7,10-tetraazacyclododecane-1,4,7,10-t...Synovial sarcoma is a relatively rare subset of soft tissue sarcoma.A male patient with an anterior mediastinal mass and multiple pulmonary nodules underwent 18F-FDG and 68Ga-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-1-NaI3-octreotide(68Ga-DOTANOC)PET/CT scans to evaluate glycometabolism and somatostatin receptor(SSTR)expression,initially suspected to be thymic neuroendocrine tumor.Increased metabolic activity was observed in all lesions,while only one pulmonary nodule showed high expression of SSTR.In addition,there was a giant mass on the patient's thigh with high FDG uptake and partially high SSTR expression.The final pathology confirmed metastatic synovial sarcoma by biopsy of the pulmonary nodule.展开更多
Although generally benign,thymomas have the potential to be malignant due to their tendency for local invasion and occasional development of distant metastases.They are characterized by infiltration and extension into...Although generally benign,thymomas have the potential to be malignant due to their tendency for local invasion and occasional development of distant metastases.They are characterized by infiltration and extension into adjacent structures,with metastasis typically confined to the pleura,pericardium,or diaphragm.In this case,a rare instance of invasive AB-type thymoma located in the anterior mediastinum is reported,which had invaded the superior vena cava and extended caudally into the right atrium.^(18)F-fluorodeoxyglucose(^(18)F-FDG)PET/CT clearly defined the size and characteristics of the lesion,providing valuable information for patient management.展开更多
Radiologists are sometimes faced with a dilemma in differentiating inflammatory mucosal thickening from malignant disease.In this case,we reported 18F-fluorodeoxyglucose(FDG)and 68Ga-fibroblast activation protein inhi...Radiologists are sometimes faced with a dilemma in differentiating inflammatory mucosal thickening from malignant disease.In this case,we reported 18F-fluorodeoxyglucose(FDG)and 68Ga-fibroblast activation protein inhibitor(FAPI)PET/CT findings in a 48-year-old patient with suspected nasopharyngeal carcinoma.18F-FDG PET/CT showed diffuse soft-tissue thickening with intense radiotracer uptake in the nasopharynx.However,no abnormal 68Ga-FAPI uptake was observed in the nasopharyngeal mass.The pathological examinations after endoscopic excision confirmed the diagnosis of inflammatory mucosal thickening of the nasopharynx.This case demonstrates that 68Ga-FAPI PET/CT may be more specific than 18F-FDG PET/CT and MRI in differentiating nasopharyngeal mucosal inflammation from nasopharyngeal carcinoma.展开更多
Background:Thymic carcinoid(ThC)is an extremely rare type of neuroendocrine tumor.Evidence for ThC evaluation with^(68)Ga-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-1-NaI³-octreotide(^(68)Ga-DOTAN...Background:Thymic carcinoid(ThC)is an extremely rare type of neuroendocrine tumor.Evidence for ThC evaluation with^(68)Ga-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-1-NaI³-octreotide(^(68)Ga-DOTANOC)and^(18)F-fluorodeoxyglucose(^(18)F-FDG)PET/CT has limitation.This study aimed to estimate the diagnostic and prognostic value of^(68)Ga-DOTANOC and^(18)F-FDG PET/CT for ThC.Methods:A total of 88 ThC patients who underwent^(68)Ga-DOTANOC PET/CT(55 of them underwent^(18)F-FDG PET/CT within 7 days)were retrospectively included.The highest SUVmax of the metastatic and primary lesions,as well as the background in blood,liver,and spleen,were measured for calculation of tumor-to-background ratio(TBR),tumor-to-liver ratio(TLR),and tumor-to-spleen ratio(TSR)for the final analysis.Correlations between immunohistochemistry(IHC)expression and PET/CT parameters were analyzed.Prognostic parameters for progression-free survival(PFS)were assessed by Cox regression analysis.Results:The positivity rates of^(68)Ga-DOTANOC and^(18)F-FDG PET/CT were 21.6%and 74.5%,respectively.Visual analysis showed a significant correlation between somatostatin receptor subtype 2(SSTR2)expression and^(68)Ga-DOTANOC PET/CT uptake(P<0.001,r=0.495).According to receiver operating characteristic(ROC)analysis,the areas under the curve(AUC)for TBR,TLR,and TSR were 0.891,0.661,and 0.673,respectively.The highest sensitivity and specificity were 87.5%and 64.5%,respectively,when defining the cutoff value of TBR as 2.9(P=0.006).However,no significant correlation was observed between the Ki-67 index and^(18)F-FDG PET parameters.^(18)F-FDG PET status was the only predictor of PFS in patients with metastatic ThCs(P=0.026,hazard ratio(HR)0.247,95%CI 0.072~0.843).Conclusions:When interpreting the^(68)Ga-DOTANOC PET/CT of ThCs,TBR might be the most accurate indicator correlated with SSTR2 expression on IHC.^(18)F-FDG PET status could predict the PFS in patients with metastatic ThCs.展开更多
文摘BACKGROUND There are no studies on incidental anal ^18F-fluorodeoxyglucose(^18FDG)uptake.AIM To assess the rate and aetiologies of incidental anal ^18FDG uptake and to evaluate the correlation between ^18FDG positron-emission tomography/computed tomography(PET/CT)parameters and the diagnosis of an anorectal disease.METHODS The data from patients with incidental anal ^18FDG uptake were retrospectively analysed.Patients who underwent anorectal examinations were identified and compared to those who did not undergo examinations.Patients who were offered treatment were then identified and compared to those who did not receive treatment.RESULTS Among the 43020^18FDG PET/CT scans performed,197^18FDG PET/CT scans of 146 patients(0.45%)reported incidental anal uptake.Among the 134 patients included,48(35.8%)patients underwent anorectal examinations,and anorectal diseases were diagnosed in 33(69.0%)of these patients and treated in ^18/48(37.5%)patients.Among the examined patients,those with a pathology requiring treatment had significantly smaller metabolic volumes(MV)30 and MV41 values and higher maximal and mean standardized uptake value measurements than those who did not require treatment.CONCLUSION Incidental anal ^18FDG uptake is rare,but a reliable anorectal diagnosis is commonly obtained when an anorectal examination is performed.The diagnosis of an anorectal disease induces treatment in more than one-third of the patients.These data should encourage practitioners to explore incidental anal ^18FDG uptake systematically.
基金supported in part by KAKENHI Grant‐in‐Aid for Scientific Research(#23K07089)from the Japan Society for the Promotion of Science.
文摘Positron emission tomography(PET)with F‐18 fluorodeoxyglucose(FDG)is an established tool in clinical molecular imaging for evaluating metabolic activity.Advanced PET systems enable high‐resolution three‐dimensional analysis of FDG distribution,offering insightful information for lesion characterization.Furthermore,dynamic whole‐body imaging facilitates assessment of temporal FDG uptake following its administration.This development introduces the concept of four‐dimensional(4D)FDG PET/CT,enhancing the precision of lesion characterization.A critical advantage of applying 4D FDG PET/CT is the ability to distinguish pathological from physiological FDG uptake by analyzing motion‐related uptake.Correcting motion and integrating serial imaging data enable accurate interpretation.Additionally,FDG uptake quantification is possible using Patlak analysis.This review discusses innovative clinical applications and quantitative techniques for analyzing FDG distribution through 4D FDG PET/CT.
基金Supported by the Tianjin Science and Technology Project,No.TJWJ2025RC008。
文摘BACKGROUND Malignant pleural mesothelioma(MPM),a rare aggressive malignancy,is primarily caused by asbestos exposure.MPM typically affects older adults(median age,76 years),is uncommon in those under age 50 years and shows male predominance.Based on the American Society of Clinical Oncology guidelines,F-18 fluorodeoxyglucose positron emission tomography/computed tomography(F-18 FDG PET/CT)is essential for initial MPM staging.Integrating quantitative FDG metabolic data with computed tomography(CT)anatomy optimizes biopsy accuracy and staging.CASE SUMMARY A 21-year-old female college student presented with fever(peak 38.4°C),cough,and white mucoid sputum after cold exposure.Initial evaluation revealed elevated C-reactive protein[C-reactive protein(CRP);65.52 mg/L]and Mycoplasma pneumoniae IgM.Despite resolution of fever following a 14-day moxifloxacin regimen,persistent cough prompted chest CT,which demonstrated left pleural mass-like thickenings.Levofloxacin therapy for 2 weeks failed to alleviate symptoms,accompanied by 2.5-kg weight loss over 1 month.Re-evaluation showed rising CRP(88.87 mg/L)with stable CT lesions,and negative T-cell spot test for tuberculosis and tumor markers.Contrast-enhanced CT revealed heterogeneously enhancing masses,while PET/CT detected two broad-based pleural lesions with intense FDG avidity.CT-guided biopsy confirmed epithelioid MPM.Thoracoscopy exposed diffuse fragile,hemorrhagic nodules implanting on diaphragmatic and parietal pleura,confirming metastatic MPM with partial resection performed.This presentation challenges conventional imaging paradigms of MPM,underscoring its diagnostic complexity.CONCLUSION MPM should still be considered an important differential diagnosis in young patients presenting with solitary pleural masses and no history of typical asbestos exposure.F-18 FDG PET/CT,while serving as an essential component of initial staging for MPM,has some inherent limitations.
基金supported by the National Natural Science Foundation of China(Grant 32027802)Key Research and Development Program of Zhejiang Province(Grant 2022C03071)+1 种基金Medical and Health Research Project of Zhejiang Province(Grant 2024KY1222)Teaching Reform Project of the Education Department of Zhejiang Province(Grant JGBA2024231).
文摘Ovarian cancer(OC)is the most lethal gynecological malignancy.Diagnosis usually occurs late,and even with the most effective treatment relapses are frequent.Early diagnosis and precise staging are critical for achieving better treatment outcomes and prognoses.Conventional imaging methods such as ultrasound(US),computed tomography(CT),and magnetic resonance imaging(MRI)are the main imaging techniques supporting management decisions.However,advancements in molecular imaging have made positron emission tomography/computed tomography(PET/CT)a promising noninvasive imaging option for better management of OC.The literature provides evidence indicating that fluorine‐18‐fluorodeoxyglucose(^(18)F‐FDG)PET/CT(FDG‐PET/CT)is effective in primary tumor diagnosis,staging,prognosis evaluation,treatment response assessment,and relapse surveillance.Looking ahead,significant attention should be paid to tracers beyond FDG,integrated PET/MRI,dynamic PET,and artificial intelligence(AI)‐based radiomics.This review examines the application of PET/CT in OC management at each disease stage and discusses its future potential.
文摘A 16‐year‐old male teenager with no prior medical history suddenly experienced right upper limb weakness.The weakness persisted for 2 weeks,followed by a headache and unstable walking.On physical examination,the patient exhibited decreased verbal fluency,a shallow right nasolabial fold,and tongue movement to the right side.Reduced muscle strength with normal muscle tension was observed in the right limb.On laboratory examination,lymphocytes were decreased,and neutrophils were slightly increased.The patient underwent brain CT,MRI,and whole‐body ^(18)F‐fluorodeoxyglucose PET/CT.Intra-cranial biopsy was performed to confirm the pathology(Figure 1).The final pathological diagnosis was the Rosai-Dorfman disease,characterized by abnormal hyperplasia of the sinuses combined with an accumulation of histiocytes in the lymph nodes.Although extranodal involvement has been reported,primary infiltration of the central nervous system is extremely rare,particularly in the brain parenchyma.
基金Supported by National Polish Science Centre,No.403238140
文摘AIM： To investigate the correlations of pre-treatmentpositron emission tomography-computer tomography（PET-CT） metabolic quantifiers with clinical data ofunstratified gastric cancer （GC） patients.METHODS： Forty PET-CT scans utilising 18-fluorodeoxyglucosein patients who received no prior treatmentwere analysed. Analysis involved measurements ofmaximum and mean standardised uptake volumes（SUV）, coefficient of variation （COV）, metabolictumour volumes and total lesion glycolysis of differentthresholds above which the tumor volumes wereidentified. The threshold values were： SUV absolutevalue of 2.5, 30% of SUVmax, 40% of SUVmax,and liver uptake-based （marked 2.5, 30, 40 and liv,respectively）. Clinical variables such as age, sex,clinical stage, performance index, weight loss, tumorhistological type and grade, and CEA and CA19.9 levelswere included in survival analysis. Patients receivedvarious treatment modalities appropriate to theirdisease stage and the outcome was defined by time tometastasis （TTM） and overall survival （OS）. Clinical andmetabolic parameters were evaluated by analysis of variance, receiver operating characteristics, univariateKaplan-Meier, and multivariate Cox models. P 〈 0.05was considered statistically significant.RESULTS： Significant differences were observedbetween initially disseminated and non-disseminatedpatients in mean SUV （6.05 vs 4.13, P = 0.008）, TLG2.5（802 cm3 vs 226 cm3; P = 0.031）, and TLG30 （436 cm3vs 247 cm3, P = 0.018）. Higher COV was associatedwith poor tumour differentiation （0.47 for G3 vs0.28 for G1 and G2; P = 0.03）. MTV2.5 was positivelycorrelated to patient weight loss （〈 5%, 5%-10%and 〉 10%： 40.4 cm3 vs 123.6 cm3 vs 181.8 cm3,respectively, P = 0.003）. In multivariate Cox analysis,TLG30 was prognostic for OS （HR = 1.001, 95%CI：1.0009-1.0017; P = 0.047） for the whole group ofpatients. In the same model yet only including patientswithout initial disease dissemination TLG30 （HR = 1.009,95%CI： 1.003-1.014; P = 0.004） and MTV2.5 （HR = 1.02,95%CI： 1.002-1.036; P = 0.025） were prognostic forOS; for TTM TLG30 was the only significant prognosticvariable （HR = 1.006, 95%CI： 1.001-1.012; P = 0.02）.CONCLUSION： PET-CT in GC may represent a valuablediagnostic and prognostic tool that requires furtherevaluation in highly standardised environments such asrandomised clinical trials.
文摘AIM To evaluate the value of pre-treatment 18F-FDG PET/CT in patients with HCC following liver radioembolization.METHODS We identified 34 patients with HCC who underwent an FDG PET/CT scan prior to hepatic radioembolization at our institution between 2009 and 2013. Patients wereseen in clinic one month after radioembolization and then at 2-3 mo intervals. We assessed the influence of FDG tumor uptake on outcomes including local liver control(LLC), distant liver control(DLC), time to distant metastases(DM), progression free survival(PFS) and overall survival(OS).RESULTS The majority of patients were males(n = 25, 74%), and had Child Pugh Class A(n = 31, 91%), with a median age of 68 years(46-84 years). FDG-avid disease was found in 19(56%) patients with SUVmax ranging from 3 to 20. Female patients were more likely to have an FDG-avid HCC(P = 0.02). Median follow up of patients following radioembolization was 12 months(1.2-62.8 mo). FDG-avid disease was associated with a decreased 1 year LLC, DLC, DM and PFS(P < 0.05). Using multivariate analysis, FDG avidity predicted for LLC, DLC, and PFS(all P < 0.05).CONCLUSION In this retrospective study, pre-treatment HCC FDGavidity was found to be associated with worse LLC, DLC, and PFS following radioembolization. Larger studies are needed to validate our initial findings to assess the role of F-18-FDG PET/CT scans as biomarker for patients with HCC following radioembolization.
文摘Recently, several reports have demonstrated that fluorine-18 fluorodeoxyglucose positron emission tomography （FDG-PET） is useful in differentiating between benign and malignant lesions in the gallbladder. However, there is a limitation in the ability of FDG-PET to differentiate between inflammatory and malignant lesions. We herein present a case of xanthogranulomatous cholecystitis misdiagnosed as gallbladder carcinoma by ultrasonography and computed tomography. FDG-PET also showed increased activity. In this case, FDG-PET findings resulted in a false-positive for the diagnosis of gallbladder carcinoma.
基金Supported by Soonchunhyang University Research Fund and Research Fund of Catholic Kwandong University International St.Mary's Hospital
文摘AIM To determine the relationship between F-18 fluorodeoxyglucose(FDG) uptake of bone marrow(BM) on positron emission tomography/computed tomography(PET/CT) and clinical factors and to assess the prognostic value of FDG uptake of BM in gastric carcinoma.METHODS We retrospectively enrolled 309 gastric cancer patients who underwent staging FDG PET/CT and curative surgical resection. FDG uptake of primary tumor was visually classified as positive or negative FDG uptake. Mean FDG uptake of BM(BM SUV) and BM-to-liver uptake ratio(BLR) were measured. The relationships of BM SUV or BLR with clinical factors were evaluated. The prognostic values of BM SUV, BLR, and other clinical factors for predicting recurrence-free survival(RFS) and overall survival(OS) were assessed.RESULTS Of 309 patients, 38 patients(12.3%) experienced cancer recurrence and 18 patients(5.8%) died. Patients with advanced gastric cancer, positive FDG uptake, and recurrence had higher values of BM SUV and BLR than those with early gastric cancer, negative FDG uptake, and no recurrence(P < 0.05). BM SUV and BLR were significantly correlated with hemoglobin level, neutrophil-to-lymphocyte ratio, and platelet-tolymphocyte ratio(P < 0.05). On multivariate analysis, multiple tumors, T stage, lymph node metastasis, tumor involvement of resection margin, and BLR were significantly associated with RFS(P < 0.05). T stage, lymph node metastasis, hemoglobin level, and BLR were significantly associated with OS(P < 0.05). CONCLUSION BLR on PET/CT was an independent prognostic factor for RFS and OS in gastric cancer patients with curative surgical resection.
文摘AIM: To evaluate the influence of baseline maximum standardized uptake value(SUVmax) on survival in a cohort of patients, undergoing positron emission tomography-computed tomography(PET-CT) scan for esophageal carcinoma. METHODS: The pre-treatment SUVmax numeric reading was determined in patients with confirmed esophageal or junctional cancer having PET-CT scan during the time period 1st January 2007 until 31 st July 2012. A minimum follow up of 12 mo was required. Patients were subdivided into quartiles according to SUVmax value and the influence of SUVmax on survival was assessed using univariate and multivariate analysis. The following pre-treatment factors were investigated: patient characteristics, tumor characteristics and planned treatment. RESULTS: The study population was 271 patients(191male) with esophageal or junctional carcinoma. The median age was 65 years(range 40-85) and histologic subtype was adenocarcinoma in 197 patients and squamous carcinoma in 74 patients. The treatment intent was radical in 182 and palliative in 89 patients. SUVmax was linked to histologic subtype(P = 0.008), tumor site(P = 0.01) and Union for International Cancer Control(UICC) stage(P < 0.001). On univariate analysis, prognosis was significantly associated with SUVmax(P = 0.001), T-stage(P < 0.001) and UICC stage(P < 0.001). On multivariate analysis, only T-stage and UICC stage remained significant. CONCLUSION: Pretreatment SUVmax was not a useful marker in isolation for determining prognosis of patients with esophageal carcinoma.
文摘BACKGROUND Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography(F-18 FDG PET/CT),a functional imaging method,is usually performed on the entire torso,and regions of unexpected suspicious focal hypermetabolism are not infrequently observed.Among the regions,colon,thyroid,and prostate were found to be the common organs in a recent umbrella review.Some studies reported that a high rate of malignancy was shown in incidentally identified focal hypermetabolic regions and suggested that further examinations should not be ignored.AIM To investigate the malignancy rate of incidental focal FDG uptake,useful PET parameters and their cutoffs in discrimination between malignant and benign lesions.METHODS Retrospectively,the final reports of 16510 F-18 FDG PET/CT scans performed at our hospital between January 2016 and March 2022 were reviewed to identify incidentally observed FDG uptake in the colon/rectum,thyroid,and prostate.The scans of patients with current or prior malignancies at each corresponding location,without the final reports of histopathology or colonoscopy(for colon and rectum)for the corresponding hypermetabolic regions,or with diffuse(not focal)hypermetabolism were excluded.Finally,88 regions of focal colorectal hypermetabolism in 85 patients(48 men and 37 women with mean age 67.0±13.4 years and 63.4±15.8 years,respectively),48 focal thyroid uptakes in 48 patients(12 men and 36 women with mean age 62.2±13.1 years and 60.8±12.4 years,respectively),and 39 focal prostate uptakes in 39 patients(mean age 71.8±7.5 years)were eligible for this study.For those unexpected focal hypermetabolic regions,rates of malignancy were calculated,PET parameters,such as standardized uptake value(SUV),capable of distinguishing between malignant and benign lesions were investigated,and the cutoffs of those PET parameters were determined by plotting receiver operating characteristic curves.RESULTS In the colon and rectum,29.5%(26/88)were malignant and 33.0%(29/88)were premalignant lesions.Both SUVmax and SUVpeak differentiated malignant/premalignant from benign lesions,however,no parameters could distinguish malignant from premalignant lesions.Higher area under the curve was shown with SUVmax(0.752,95%CI:0.649-0.856,P<0.001)and the cutoff was 7.6.In the thyroid,60.4%(29/48)were malignant.The majority were well-differentiated thyroid cancers(89.7%,26/29).The results of BRAF mutation tests were available for 20 of the 26 welldifferentiated thyroid cancers and all 20 had the mutation.Solely SUVmax differentiated malignant from benign lesions and the cutoff was 6.9.In the prostate,56.4%(22/39)were malignant.Only SUVmax differentiated malignant from benign lesions and the cutoff was 3.8.Overall,among the 175 focal hypermetabolic regions,60.6%(106/175)were proven to be malignant and premalignant(in colon and rectum)lesions.CONCLUSION Approximately 60%of the incidentally observed focal F-18 FDG uptake in the colon/rectum,thyroid,and prostate were found to be malignant.Of the several PET parameters,SUVmax was superior to others in distinguishing between malignant/premalignant and benign lesions.Based on these findings,incidental focal hypermetabolism should not be ignored and lead physicians to conduct further investigations with greater confidence.
文摘AIM To determine the significance and need for investigation of incidental prostatic uptake in men undergoing ^(18)F-labelled fluorodeoxyglucose(^(18)F-FDG) positron emission tomography/computed tomography(PET/CT) for other indications.METHODS Hospital databases were searched over a 5-year period for patients undergoing both PET/CT and prostate magnetic resonance imaging(MRI). For the initial analysis, the prostate was divided into six sectors and suspicious or malignant sectors were identified using MRI and histopathology reports respectively. Maximum and mean ^(18)F-FDG standardised uptake values were measured in each sector by an investigator blinded to the MRI and histopathology findings. Two agematched controls were selected per case. Results were analysed using a paired t-test and one-way ANOVA. For the second analysis, PET/CT reports were searched for prostatic uptake reported incidentally and these patients were followed up. RESULTS Over a 5-year period, 15 patients underwent both PET/CT and MRI and had biopsy-proven prostate cancer.Malignant prostatic sectors had a trend to higher ^(18)F-FDG uptake than benign sectors, however this was neither clinically nor statistically significant(3.13 ±0.58 vs 2.86 ± 0.68, P > 0.05). ^(18)F-FDG uptake showed no correlation with the presence or histopathological grade of tumour. ^(18)F-FDG uptake in cases with prostate cancer was comparable to that from age-matched controls. Forty-six(1.6%) of 2846 PET/CTs over a 5-year period reported incidental prostatic uptake. Of these, 18(0.6%) were investigated by PSA, 9(0.3%)were referred to urology, with 3(0.1%) undergoing MRI and/or biopsy. No cases of prostate cancer were diagnosed in patients with incidental ^(18)F-FDG uptake in our institute over a 5-year period.CONCLUSION ^(18)F-FDG uptake overlaps significantly between malignant and benign prostatic conditions. Subsequent patient management was not affected by the reporting of incidental focal prostatic uptake in this cohort.
基金National Health Institute of Spain:ISCIII Grant PI11/02035 and DTS14/00188BIOCAPS project(FP7/REGPOT-2012-2013.1),No.316265+1 种基金MSKCC internal IMRAS grantin part through the NIH/NCI Cancer Center,No.P30 CA008748
文摘AIMTo noninvasively investigate tumor cellularity measured using diffusion-weighted magnetic resonance imaging(DW-MRI)and glucose metabolism measured by<sup>18</sup>F-labeled fluorodeoxyglucose positron emission tomography/computed tomography(<sup>18</sup>F-FDG-PET/CT)during radiation therapy(RT)for human papillomavirus negative(HPV-)head and neck squamous cell carcinoma(HNSCC).METHODSIn this prospective study,6 HPV-HNSCC patients underwent a total of 34 multimodality imaging examinations DW-MRI at 1.5 T Philips MRI scanner[(n=24)pre-,during-(2-3 wk),and post-treatment(Tx),and<sup>18</sup>F-FDG PET/CT pre-and post-Tx(n=10)].All patients received RT.Monoexponential modeling of the DW-MRI data yielded the imaging metric apparent diffusion coefficient(ADC)and the mean of standardized uptake value(SUV)was measured from<sup>18</sup>F-FDG PET uptake.All patients had a clinical follow-up as the standard of care and survival status was documented at 1 year.RESULTSThere was a strong negative correlation between the mean of pretreatment ADC(ρ=-0.67,P=0.01)and the pretreatment<sup>18</sup>F-FDG PET SUV.The percentage(%)change in delta(∆)ADC for primary tumors and neck nodal metastases between pre-and Wk<sub>2-3</sub>Tx were as follows:75.4%and 61.6%,respectively,for the patient with no evidence of disease,27.5%and 32.7%,respectively,for those patients who were alive with disease,and 26.9%and 7.31%,respectively,for those who were dead with disease.CONCLUSIONThese results are preliminary in nature and are indicative,and not definitive,trends rendered by the imaging metrics due to the small sample size of HPV-HNSCC patients in a Meixoeiro Hospital of Vigo Experience.
文摘BACKGROUND Colon and rectal cancers are among the top five cancers worldwide in terms of their incidence and mortality rates.As the treatment options for cure include surgery even in specific advanced-stage cases,the early detection of lesions is important for applying active treatment methods.Fluorine-18 fluorodeoxyglucose(F-18 FDG)positron emission tomography/computed tomography(PET/CT)is an established imaging study for many types of cancers;however,physiologic uptake in the gastrointestinal tract is a frequent finding and may interfere with lesion identification.Nevertheless,as unexpectedly observed focal colorectal F-18 FDG uptake may harbor malignant lesions,further examination must not be avoided.AIM To assess the clinical implications of unexpected focal colorectal F-18 FDG uptake by analyzing FDG PET parameters.METHODS A total of 15143 F-18 FDG PET/CT scans performed at our hospital between January 2016 and September 2021 were retrospectively reviewed to identify incidentally observed focal colorectal FDG uptake.Finally,83 regions showing focal colorectal FDG uptake with final histopathological reports from 80 patients(45 men and 35 women with mean ages of 66.9±10.7 years and 63.7±15.3 years,respectively)were eligible for inclusion in the present study.Each focal hypermetabolic colorectal region was classified as malignant,premalignant,or benign according to the histopathological report.PET parameters such as maximum and peak standardized uptake value(SUVmax and SUVpeak),metabolic tumor volume(MTV),mean SUV of the metabolic tumor volume(mSUVmtv),and total lesion glycolysis(TLG)were measured or calculated for the corresponding hypermetabolic regions.Parametric and nonparametric statistical comparisons of these parameters were performed among the three groups.Receiver operating characteristic curves were plotted to identify cut-off values.RESULTS The detection rate of incidental focal colorectal uptake was 0.53%(80/15,143).Of the 83 regions with unexpected focal colorectal hypermetabolism,28.9%(24/83)were malignant,32.5%(27/83)were premalignant,and 38.6%(32/83)were benign.Overall,61.4% of the regions had malignant or premalignant lesions.SUVmax,SUVpeak,and mSUVmtv differentiated malignant and/or premalignant lesions from benign lesions with statistical significance(P<0.05).mSUVmtv3.5 differentiated malignant from benign lesions,with the largest area under the curve(AUC)of 0.792 and a cut-off of 4.9.SUVmax showed the largest AUC of 0.758 with a cut-off value of 7.5 for distinguishing between premalignant and benign lesions.Overall,SUVmax with a cut-off value of 7.6(AUC:0.770,95% confidence interval(CI):0.668-0.872;sensitivity,0.686;specificity,0.688)was a superior parameter for distinguishing between malignant/premalignant and benign lesions or physiologic uptake.No parameters differentiated malignant from premalignant lesions.Moderate or weak positive correlations were observed between the long diameter of the malignant lesions and PET parameters such as SUVpeak and some mSUVmtv.CONCLUSION Approximately two-thirds(61.4%)of incidental focal hypermetabolic colorectal regions were malignant/premalignant lesions,for which SUVmax was an independent diagnostic parameter.Unexpected suspicious focal colorectal FDG uptake should not be avoided and consideration for further evaluation is strongly recommended not to miss the two-thirds.
基金Supported by the Tianjin Science and Technology Project,No.16ZXMJSY00170.
文摘BACKGROUND Lymphangioma is a rare benign cystic tumor believed to be a proliferation of heterotopic lymphocytes.It is caused by congenital lymphatic dysplasia or other acquired factors related to surgery,trauma,infection,or cancer.In this article,we present the case of an adult patient who underwent multi-modal imaging and whose condition was finally confirmed to be multiple cystic lymphangiomas by pathological examination.CASE SUMMARY A 61-year-old man was referred to our hospital for having suffered from painless gross hematuria for 2 wk.Multiple masses rising from the retroperitoneum and pelvis were found incidentally by urinary ultrasonography.Contrast-enhanced abdominal-pelvic computed tomography showed multiple well-defined hypodense cystic lesions without enhancement.The lesions showed no uptake on F-18-fluorodeoxyglucose positron emission tomography/computed tomography images.Exploratory laparotomy was performed,and the case was confirmed as multiple cystic lymphangiomas.CONCLUSION When retroperitoneal and pelvic masses are found,clinicians should always consider cystic lymphangioma when making a differential diagnosis.
文摘BACKGROUND Diagnosis of prosthetic vascular graft infection with[(18)F]fluorodeoxyglucose positron emission tomography/computed tomography(18F-FDG PET/CT)allows for early detection of functional changes associated with infection,based on increased glucose utilization by activated macrophages and granulocytes.Aseptic vascular grafts,like all foreign bodies,can stimulate an inflammatory response,which can present as increased activity on 18F-FDG PET/CT.Consequently,distinguishing aseptic inflammation from graft infection,though important,can be difficult.In the case of endovascular aneurysm repair(EVAR),a minimally invasive procedure involving the transfemoral insertion of an endoprosthetic stent graft,the normal postoperative appearance of these grafts on 18F-FDG PET/CT can vary over time,potentially confounding study interpretation.AIM To investigate the visual,semiquantitative,and temporal characteristics of aseptic vascular grafts in patients status post EVAR.METHODS In this observational retrospective cohort study,patients with history of EVAR who underwent 18F-FDG PET/CT for indications other than infection were identified retrospectively.All patients were asymptomatic for graft infection-no abdominal pain,fever of unknown origin,sepsis,or leukocytosis-at the time of imaging and for≥2 mo after each PET/CT.Imaging studies such as CT for each patient were also reviewed,and any patients with suspected or confirmed vascular graft infection were excluded.One hundred two scans performed on 43 patients(34 males;9 females;age=77±8 years at the time of the final PET/CT)were retrospectively reviewed.All 43 patients had an abdominal aortic(AA)vascular graft,40 patients had a right iliac(RI)limb graft,and 41 patients had a left iliac(LI)limb graft.Twentytwo patients had 1 PET/CT and 21 patients had from 2 to 9 PET/CTs.Grafts were imaged between 2 mo to 168 mo(about 14 years)post placement.Eight grafts were imaged within 6 mo of placement,including three that were imaged within three months of placement.The mean interval between graft placement and PET/CT for all 102 scans was 51±39 mo.PET/CT data was reconstructed with region-of-interest analysis of proximal,mid and distal portions of the grafts and background ascending aorta.Maximum standardized uptake value(SUVmax)was recorded for each region.SUVmax-to-background uptake ratios(URs)were calculated.Visual assessment was performed using a 2-pattern grading scale:Diffuse(homogeneous uptake less than liver uptake)and focal(one or more areas of focal uptake in any part of the graft).Statistical analysis was performed.RESULTS In total,there were 306 AA grafts,285 LI grafts,282 RI grafts,and 306 ascending aorta background SUVmax measurements.For all 102 scans,mean SUVmax values for AA grafts were 2.8-3.0 along proximal,mid,and distal segments.Mean SUVmax values for LI grafts and RI grafts were 2.7-2.8.Mean SUVmax values for background were 2.5±0.5.Mean URs were 1.1-1.2.Visual analysis of the scans reflected results of quantitative analysis.On visual inspection,98%revealed diffuse,homogeneous 18F-FDG uptake less than liver.Graft URs and visual pattern categories were significantly associated for AA graft URs(F-ratio=21.5,P<0.001),LI graft URs(F-ratio=20.4,P<0.001),and RI graft URs(F-ratio=30.4,P<0.001).Thus,visual patterns of 18F-FDG uptake corresponded statistically significantly to semiquantitative URs.The age of grafts showing focal patterns was greater than grafts showing diffuse patterns,87±89 vs 50±37 mo,respectively(P=0.02).URs were significantly associated with graft age for AA grafts(r=0.19,P=0.001).URs were also significantly associated with graft age for LI grafts(r=0.25,P<0.0001),and RI grafts(r=0.31,P<0.001).Quartiles of similar numbers of graft(n=25-27)grouped by graft age indicated that URs were significantly higher for 4th quartile vs 2nd quartile URs(F-ratio=19.5,P<0.001).When evaluating URs,graft SUVmax values within 10%-20%of the ascending aorta SUVmax is evident in aseptic grafts,except for grafts in the oldest quartiles.In this study,grafts in the oldest quartiles(>7 years post EVAR)showed SUVmax up to 30%higher than the ascending aorta SUVmax.CONCLUSION Characteristics of an aseptic vascular stent graft in the aorta and iliac vessels on 18F-FDG PET/CT include graft SUVmax values within 10%-20%of the ascending aorta background SUVmax.The SUVmax of older aseptic grafts can be as much as 30%above background.The visual uptake pattern of diffuse,homogeneous uptake less than liver was seen in 98%of aseptic vascular grafts,making this pattern particularly reassuring for clinicians.
文摘Synovial sarcoma is a relatively rare subset of soft tissue sarcoma.A male patient with an anterior mediastinal mass and multiple pulmonary nodules underwent 18F-FDG and 68Ga-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-1-NaI3-octreotide(68Ga-DOTANOC)PET/CT scans to evaluate glycometabolism and somatostatin receptor(SSTR)expression,initially suspected to be thymic neuroendocrine tumor.Increased metabolic activity was observed in all lesions,while only one pulmonary nodule showed high expression of SSTR.In addition,there was a giant mass on the patient's thigh with high FDG uptake and partially high SSTR expression.The final pathology confirmed metastatic synovial sarcoma by biopsy of the pulmonary nodule.
文摘Although generally benign,thymomas have the potential to be malignant due to their tendency for local invasion and occasional development of distant metastases.They are characterized by infiltration and extension into adjacent structures,with metastasis typically confined to the pleura,pericardium,or diaphragm.In this case,a rare instance of invasive AB-type thymoma located in the anterior mediastinum is reported,which had invaded the superior vena cava and extended caudally into the right atrium.^(18)F-fluorodeoxyglucose(^(18)F-FDG)PET/CT clearly defined the size and characteristics of the lesion,providing valuable information for patient management.
基金funded by the National Natural Science Foundation of China(No.82422039).
文摘Radiologists are sometimes faced with a dilemma in differentiating inflammatory mucosal thickening from malignant disease.In this case,we reported 18F-fluorodeoxyglucose(FDG)and 68Ga-fibroblast activation protein inhibitor(FAPI)PET/CT findings in a 48-year-old patient with suspected nasopharyngeal carcinoma.18F-FDG PET/CT showed diffuse soft-tissue thickening with intense radiotracer uptake in the nasopharynx.However,no abnormal 68Ga-FAPI uptake was observed in the nasopharyngeal mass.The pathological examinations after endoscopic excision confirmed the diagnosis of inflammatory mucosal thickening of the nasopharynx.This case demonstrates that 68Ga-FAPI PET/CT may be more specific than 18F-FDG PET/CT and MRI in differentiating nasopharyngeal mucosal inflammation from nasopharyngeal carcinoma.
文摘Background:Thymic carcinoid(ThC)is an extremely rare type of neuroendocrine tumor.Evidence for ThC evaluation with^(68)Ga-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-1-NaI³-octreotide(^(68)Ga-DOTANOC)and^(18)F-fluorodeoxyglucose(^(18)F-FDG)PET/CT has limitation.This study aimed to estimate the diagnostic and prognostic value of^(68)Ga-DOTANOC and^(18)F-FDG PET/CT for ThC.Methods:A total of 88 ThC patients who underwent^(68)Ga-DOTANOC PET/CT(55 of them underwent^(18)F-FDG PET/CT within 7 days)were retrospectively included.The highest SUVmax of the metastatic and primary lesions,as well as the background in blood,liver,and spleen,were measured for calculation of tumor-to-background ratio(TBR),tumor-to-liver ratio(TLR),and tumor-to-spleen ratio(TSR)for the final analysis.Correlations between immunohistochemistry(IHC)expression and PET/CT parameters were analyzed.Prognostic parameters for progression-free survival(PFS)were assessed by Cox regression analysis.Results:The positivity rates of^(68)Ga-DOTANOC and^(18)F-FDG PET/CT were 21.6%and 74.5%,respectively.Visual analysis showed a significant correlation between somatostatin receptor subtype 2(SSTR2)expression and^(68)Ga-DOTANOC PET/CT uptake(P<0.001,r=0.495).According to receiver operating characteristic(ROC)analysis,the areas under the curve(AUC)for TBR,TLR,and TSR were 0.891,0.661,and 0.673,respectively.The highest sensitivity and specificity were 87.5%and 64.5%,respectively,when defining the cutoff value of TBR as 2.9(P=0.006).However,no significant correlation was observed between the Ki-67 index and^(18)F-FDG PET parameters.^(18)F-FDG PET status was the only predictor of PFS in patients with metastatic ThCs(P=0.026,hazard ratio(HR)0.247,95%CI 0.072~0.843).Conclusions:When interpreting the^(68)Ga-DOTANOC PET/CT of ThCs,TBR might be the most accurate indicator correlated with SSTR2 expression on IHC.^(18)F-FDG PET status could predict the PFS in patients with metastatic ThCs.
