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
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
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
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 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 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
Backgroud Fluorine-18-fluorodeoxyglucose （18F-FDG） positron emission tomography imaging can be used to assess the treatment efficacy of chemotherapy and prognosis.The aim of this study was to determine the uptake ra...Backgroud Fluorine-18-fluorodeoxyglucose （18F-FDG） positron emission tomography imaging can be used to assess the treatment efficacy of chemotherapy and prognosis.The aim of this study was to determine the uptake rate of 18F-FDG in colon cancer HCT-116 cells,and to evaluate the treatment efficacy of chemotherapy,hyperthermia and thermo-chemotherapy through the uptake inhibition rate of 18F-FDG.Methods The uptake rate of 18F-FDG in HCT-116 ceils was determined at various experimental conditions.The inhibition rate of cell growth,uptake rate of 18F-FDG and uptake inhibition rate of l8F-FDG in HCT-116 cells treated with 5-fluorouracil （5-FU） at various concentrations were determined.In HCT-116 cells subjected to chemotherapy （5-FU,100 μg/ml）,hyperthermia （43℃,40 minutes） and thermo-chemotherapy for 24 hours,the inhibition rate of cell growth and uptake inhibition rate of 18F-FDG were determined; early apoptosis,the morphology and ultrastructure of HCT-116 cells were examined; and the contents of glucose and lactate dehydrogenase （LDH） in the cell culture medium of HCT-116 cells were determined.One-way analysis of variance （ANOVA） and correlation analyses were conducted by using SPSS 16.0 software.Results The uptake rate of 18F-FDG in HCT-116 cells was （44.25±2.19）%.Under the condition of adding 5-FU at various concentrations for 24 hours,the uptake rate of 18F-FDG was negatively correlated with 5-FU dosage （r=-0.879,P 〈0.01）; the inhibition rate of cell growth revealed a positive correlation with the uptake inhibition rate of 18F-FDG （r=0.831,P 〈0.01）.In HCT-116 cells subjected to hyperthermia,chemotherapy,and thermo-chemotherapy for 24 hours,the uptake inhibition rates of 18F-FDG were （12.94±2.80）%,（28.25±4.59）%,and （21.60±3.68）%,respectively.The early apoptotic rates of HCT-116 cells were （9.80±0.16）%,（19.80±2.40）%,and （15.70±1.80）%,respectively.Moreover,the contents of glucose and LDH in cell culture medium of HCT-116 cells after treatments were higher than those before treatment.Conclusion The uptake inhibition rate of 18F-FDG can be used for early evaluation of hyperthermia and 5-FU treatment efficacy on cancer cells although hyperthermia （43℃,40 minutes） does not reveal the synergistic effect on 5-FU at the low dosage.展开更多
OBJECTIVES:The objectives of this study were to investigate the clinical application of^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography(^(18)F-FDG-PET/CT)combined with CT angiography(CTA)fusi...OBJECTIVES:The objectives of this study were to investigate the clinical application of^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography(^(18)F-FDG-PET/CT)combined with CT angiography(CTA)fusion images at diagnosis and assessment in large-vessel vasculitis(LVV).MATERIALS AND METHODS:Forty-six patients with LVV who underwent both^(18)F-FDG-PET/CT and CTA procedures were studied in the Second Hospital of Harbin Medical University from September 2019 to June 2022,and the clinical disease activity of patients was judged by the Physician Global Assessment.Clinical data,acute-phase reactants(APRs),and imaging data were collected.Meanwhile,the APRS must be obtained within 1 week of^(18)F-FDG-PET/CT.^(18)F-FDG-PET/CT was primarily used to evaluate LVV activity,while CTA was primarily used to observe morphological changes in arteries,including arterial wall thickening,narrowing,and corresponding complications.PET/CT images were evaluated by two nuclear medicine physicians,both of them unaware of the patients’laboratory tests and clinical signs.Two nuclear medicine specialists evaluated the PET/CT images and PET/CTA images,who were blinded to the patients’information.The concordance of two physicians in the LVV visual grading scale was studied by calculating the Cohen’s kappa index(k)which evaluates the power of concordance.The paired t-test was used to analyze the differences between PET/CTA images and PET/CT images.RESULTS:The sensitivity and specificity of the semi-quantitative analysis to assess LVV activity was 94.1%and 93.1%,respectively,when a cutoff of the mean SUVmax/SUVmeanliver of 1.15.It was found that the images obtained after delayed phase were clearer and the contrast between the arterial wall and the lumen was higher in 19 patients.We also concluded that PET/CTA examinations were able to detect more lesion sites compared to PET/CT examinations in 28 patients(P<0.001),especially for patients with long-term treatment,and the interpretation of PET/CTA images took less time than PET/CT images(P<0.001),ultimately achieving a shorter time,more comprehensive and accurate interpretation.CONCLUSION:Although^(18)F-FDG-PET/CT can assess the activity of LVV,it is poor at observing morphological changes in arteries.The use of^(18)F-FDG-PET/CTA imaging scans in LVV can accurately assess disease activity while at the same time providing a comprehensive,accurate,and efficient determination of disease severity,allowing patients to receive comprehensive diagnostic information from PET/CTA examination.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
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
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
A 57-year-old male with a history of post-treatment esophageal squamous-cell carcinoma(ESCC)complained of a progressive headache.Suspecting tumor metastasis,this patient underwent ^(18)F-fluorodeoxyglucose(^(18)FFDG)a...A 57-year-old male with a history of post-treatment esophageal squamous-cell carcinoma(ESCC)complained of a progressive headache.Suspecting tumor metastasis,this patient underwent ^(18)F-fluorodeoxyglucose(^(18)FFDG)and ^(68)Ga-fibroblast activation protein inhibitor(^(68)Ga-FAPI)PET/CT scans as part of an investigator-initiated trial(NCT04416165).An increase of ^(18)F-FDG and ^(68)Ga-FAPI uptake was observed in the left nasal cavity,which was confirmed as metastatic ESCC by nasal endoscopy biopsy.Additionally,several scattered lesions with increased ^(68)Ga-FAPI uptake were observed in the brain.These lesions were subsequently confirmed as brain metastases by contrast-enhanced MRI.In this case,^(68)Ga-FAPI PET/CT showed superiority over ^(18)F-FDG in detecting uncommon metastases from ESCC,especially for identifying brain metastases.展开更多
Interstitial lung disease(ILD)is a common manifestation of connective tissue disease(CTD)and a substantial contributor to increased morbidity and mortality.^(18)F-fluorodeoxyglucose(^(18)F-FDG)PET/CT and^(99m)Tc-HYNIC...Interstitial lung disease(ILD)is a common manifestation of connective tissue disease(CTD)and a substantial contributor to increased morbidity and mortality.^(18)F-fluorodeoxyglucose(^(18)F-FDG)PET/CT and^(99m)Tc-HYNICfibroblast activation protein inhibitor(^(99m)Tc-HFAPI)SPECT/CT were performed on a 25-year-old female patient with systemic sclerosis-associated ILD.Baseline imaging demonstrated increased uptake of both tracers in the peripheral lung parenchyma.After corticosteroids and antifibrotic agent treatment,worsening respiratory symptoms and declining pulmonary function were observed.Follow-up imaging showed reduced FDG uptake but increased and expanded HFAPI uptake,with no significant changes on high-resolution CT(HRCT).The discrepancy between FDG and HFAPI uptake indicated the heterogeneous fibrotic and inflammatory processes occurring in individual patients.展开更多
Background:Texture analysis(TA)can quantify intra-tumor heterogeneity using standard medical images.The present study aimed to assess the application of positron emission tomography(PET)TA in the differential diagnosi...Background:Texture analysis(TA)can quantify intra-tumor heterogeneity using standard medical images.The present study aimed to assess the application of positron emission tomography(PET)TA in the differential diagnosis of gastric cancer and gastric lymphoma.Methods:The pre-treatment PET images of 79 patients(45 gastric cancer,34 gastric lymphoma)between January 2013 and February 2018 were retrospectively reviewed.Standard uptake values(SUVs),first-order texture features,and second-order texture features of the grey-level co-occurrence matrix(GLCM)were analyzed.The differences in features among different groups were analyzed by the two-way Mann-Whitney test,and receiver operating characteristic(ROC)analysis was used to estimate the diagnostic efficacy.Results:InertiaGLCM was significantly lower in gastric cancer than that in gastric lymphoma(4975.61 vs.11,425.30,z=-3.238,P=0.001),and it was found to be the most discriminating texture feature in differentiating gastric lymphoma and gastric cancer.The area under the curve(AUC)of inertiaGLCM was higher than the AUCs of SUVmax and SUVmean(0.714 vs.0.649 and 0.666,respectively).SUVmax and SUVmean were significantly lower in low-grade gastric lymphoma than those in high grade gastric lymphoma(3.30 vs.11.80,2.40 vs.7.50,z=-2.792 and-3.007,P=0.005 and 0.003,respectively).SUVs and first-order greylevel intensity features were not significantly different between low-grade gastric lymphoma and gastric cancer.EntropyGLCM12 was significantly lower in low-grade gastric lymphoma than that in gastric cancer(6.95 vs.9.14,z=-2.542,P=0.011)and had an AUC of 0.770 in the ROC analysis of differentiating low-grade gastric lymphoma and gastric cancer.Conclusions:InertiaGLCM and entropyGLCM were the most discriminating features in differentiating gastric lymphoma from gastric cancer and low-grade gastric lymphoma from gastric cancer,respectively.PET TA can improve the differential diagnosis of gastric neoplasms,especially in tumors with similar degrees of fluorodeoxyglucose uptake.展开更多
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.
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.
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.
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.
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Backgroud Fluorine-18-fluorodeoxyglucose （18F-FDG） positron emission tomography imaging can be used to assess the treatment efficacy of chemotherapy and prognosis.The aim of this study was to determine the uptake rate of 18F-FDG in colon cancer HCT-116 cells,and to evaluate the treatment efficacy of chemotherapy,hyperthermia and thermo-chemotherapy through the uptake inhibition rate of 18F-FDG.Methods The uptake rate of 18F-FDG in HCT-116 ceils was determined at various experimental conditions.The inhibition rate of cell growth,uptake rate of 18F-FDG and uptake inhibition rate of l8F-FDG in HCT-116 cells treated with 5-fluorouracil （5-FU） at various concentrations were determined.In HCT-116 cells subjected to chemotherapy （5-FU,100 μg/ml）,hyperthermia （43℃,40 minutes） and thermo-chemotherapy for 24 hours,the inhibition rate of cell growth and uptake inhibition rate of 18F-FDG were determined; early apoptosis,the morphology and ultrastructure of HCT-116 cells were examined; and the contents of glucose and lactate dehydrogenase （LDH） in the cell culture medium of HCT-116 cells were determined.One-way analysis of variance （ANOVA） and correlation analyses were conducted by using SPSS 16.0 software.Results The uptake rate of 18F-FDG in HCT-116 cells was （44.25±2.19）%.Under the condition of adding 5-FU at various concentrations for 24 hours,the uptake rate of 18F-FDG was negatively correlated with 5-FU dosage （r=-0.879,P 〈0.01）; the inhibition rate of cell growth revealed a positive correlation with the uptake inhibition rate of 18F-FDG （r=0.831,P 〈0.01）.In HCT-116 cells subjected to hyperthermia,chemotherapy,and thermo-chemotherapy for 24 hours,the uptake inhibition rates of 18F-FDG were （12.94±2.80）%,（28.25±4.59）%,and （21.60±3.68）%,respectively.The early apoptotic rates of HCT-116 cells were （9.80±0.16）%,（19.80±2.40）%,and （15.70±1.80）%,respectively.Moreover,the contents of glucose and LDH in cell culture medium of HCT-116 cells after treatments were higher than those before treatment.Conclusion The uptake inhibition rate of 18F-FDG can be used for early evaluation of hyperthermia and 5-FU treatment efficacy on cancer cells although hyperthermia （43℃,40 minutes） does not reveal the synergistic effect on 5-FU at the low dosage.
文摘OBJECTIVES:The objectives of this study were to investigate the clinical application of^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography(^(18)F-FDG-PET/CT)combined with CT angiography(CTA)fusion images at diagnosis and assessment in large-vessel vasculitis(LVV).MATERIALS AND METHODS:Forty-six patients with LVV who underwent both^(18)F-FDG-PET/CT and CTA procedures were studied in the Second Hospital of Harbin Medical University from September 2019 to June 2022,and the clinical disease activity of patients was judged by the Physician Global Assessment.Clinical data,acute-phase reactants(APRs),and imaging data were collected.Meanwhile,the APRS must be obtained within 1 week of^(18)F-FDG-PET/CT.^(18)F-FDG-PET/CT was primarily used to evaluate LVV activity,while CTA was primarily used to observe morphological changes in arteries,including arterial wall thickening,narrowing,and corresponding complications.PET/CT images were evaluated by two nuclear medicine physicians,both of them unaware of the patients’laboratory tests and clinical signs.Two nuclear medicine specialists evaluated the PET/CT images and PET/CTA images,who were blinded to the patients’information.The concordance of two physicians in the LVV visual grading scale was studied by calculating the Cohen’s kappa index(k)which evaluates the power of concordance.The paired t-test was used to analyze the differences between PET/CTA images and PET/CT images.RESULTS:The sensitivity and specificity of the semi-quantitative analysis to assess LVV activity was 94.1%and 93.1%,respectively,when a cutoff of the mean SUVmax/SUVmeanliver of 1.15.It was found that the images obtained after delayed phase were clearer and the contrast between the arterial wall and the lumen was higher in 19 patients.We also concluded that PET/CTA examinations were able to detect more lesion sites compared to PET/CT examinations in 28 patients(P<0.001),especially for patients with long-term treatment,and the interpretation of PET/CTA images took less time than PET/CT images(P<0.001),ultimately achieving a shorter time,more comprehensive and accurate interpretation.CONCLUSION:Although^(18)F-FDG-PET/CT can assess the activity of LVV,it is poor at observing morphological changes in arteries.The use of^(18)F-FDG-PET/CTA imaging scans in LVV can accurately assess disease activity while at the same time providing a comprehensive,accurate,and efficient determination of disease severity,allowing patients to receive comprehensive diagnostic information from PET/CTA examination.
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.
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.
文摘A 57-year-old male with a history of post-treatment esophageal squamous-cell carcinoma(ESCC)complained of a progressive headache.Suspecting tumor metastasis,this patient underwent ^(18)F-fluorodeoxyglucose(^(18)FFDG)and ^(68)Ga-fibroblast activation protein inhibitor(^(68)Ga-FAPI)PET/CT scans as part of an investigator-initiated trial(NCT04416165).An increase of ^(18)F-FDG and ^(68)Ga-FAPI uptake was observed in the left nasal cavity,which was confirmed as metastatic ESCC by nasal endoscopy biopsy.Additionally,several scattered lesions with increased ^(68)Ga-FAPI uptake were observed in the brain.These lesions were subsequently confirmed as brain metastases by contrast-enhanced MRI.In this case,^(68)Ga-FAPI PET/CT showed superiority over ^(18)F-FDG in detecting uncommon metastases from ESCC,especially for identifying brain metastases.
基金supported by the National Key Research and Development Program of China(No.2024YFC2419400)National Natural Science Foundation of China(No.U24A20758)National High Level Hospital Clinical Research Funding(No.2022-PUMCH-D-001).
文摘Interstitial lung disease(ILD)is a common manifestation of connective tissue disease(CTD)and a substantial contributor to increased morbidity and mortality.^(18)F-fluorodeoxyglucose(^(18)F-FDG)PET/CT and^(99m)Tc-HYNICfibroblast activation protein inhibitor(^(99m)Tc-HFAPI)SPECT/CT were performed on a 25-year-old female patient with systemic sclerosis-associated ILD.Baseline imaging demonstrated increased uptake of both tracers in the peripheral lung parenchyma.After corticosteroids and antifibrotic agent treatment,worsening respiratory symptoms and declining pulmonary function were observed.Follow-up imaging showed reduced FDG uptake but increased and expanded HFAPI uptake,with no significant changes on high-resolution CT(HRCT).The discrepancy between FDG and HFAPI uptake indicated the heterogeneous fibrotic and inflammatory processes occurring in individual patients.
文摘Background:Texture analysis(TA)can quantify intra-tumor heterogeneity using standard medical images.The present study aimed to assess the application of positron emission tomography(PET)TA in the differential diagnosis of gastric cancer and gastric lymphoma.Methods:The pre-treatment PET images of 79 patients(45 gastric cancer,34 gastric lymphoma)between January 2013 and February 2018 were retrospectively reviewed.Standard uptake values(SUVs),first-order texture features,and second-order texture features of the grey-level co-occurrence matrix(GLCM)were analyzed.The differences in features among different groups were analyzed by the two-way Mann-Whitney test,and receiver operating characteristic(ROC)analysis was used to estimate the diagnostic efficacy.Results:InertiaGLCM was significantly lower in gastric cancer than that in gastric lymphoma(4975.61 vs.11,425.30,z=-3.238,P=0.001),and it was found to be the most discriminating texture feature in differentiating gastric lymphoma and gastric cancer.The area under the curve(AUC)of inertiaGLCM was higher than the AUCs of SUVmax and SUVmean(0.714 vs.0.649 and 0.666,respectively).SUVmax and SUVmean were significantly lower in low-grade gastric lymphoma than those in high grade gastric lymphoma(3.30 vs.11.80,2.40 vs.7.50,z=-2.792 and-3.007,P=0.005 and 0.003,respectively).SUVs and first-order greylevel intensity features were not significantly different between low-grade gastric lymphoma and gastric cancer.EntropyGLCM12 was significantly lower in low-grade gastric lymphoma than that in gastric cancer(6.95 vs.9.14,z=-2.542,P=0.011)and had an AUC of 0.770 in the ROC analysis of differentiating low-grade gastric lymphoma and gastric cancer.Conclusions:InertiaGLCM and entropyGLCM were the most discriminating features in differentiating gastric lymphoma from gastric cancer and low-grade gastric lymphoma from gastric cancer,respectively.PET TA can improve the differential diagnosis of gastric neoplasms,especially in tumors with similar degrees of fluorodeoxyglucose uptake.
