BACKGROUND Primary liver cancer is a malignant tumor with a high recurrence rate that significantly affects patient prognosis.Postoperative adjuvant external radiation therapy(RT)has been shown to effectively prevent ...BACKGROUND Primary liver cancer is a malignant tumor with a high recurrence rate that significantly affects patient prognosis.Postoperative adjuvant external radiation therapy(RT)has been shown to effectively prevent recurrence after liver cancer resection.However,there are multiple RT techniques available,and the differ-ential effects of these techniques in preventing postoperative liver cancer re-currence require further investigation.AIM To assess the advantages and disadvantages of various adjuvant external RT methods after liver resection based on overall survival(OS)and disease-free survival(DFS)and to determine the optimal strategy.METHODS This study involved network meta-analyses and followed the PRISMA guidelines.The data of qualified studies published before July 10,2023,were collected from PubMed,Embase,the Web of Science,and the Cochrane Library.We included relevant studies on postoperative external beam RT after liver resection that had OS and DFS as the primary endpoints.The magnitudes of the effects were determined using risk ratios with 95%confidential intervals.The results were analyzed using R software and STATA software.RESULTS A total of 12 studies,including 1265 patients with hepatocellular carcinoma(HCC)after liver resection,were included in this study.There was no significant heterogeneity in the direct paired comparisons,and there were no significant differences in the inclusion or exclusion criteria,intervention measures,or outcome indicators,meeting the assumptions of heterogeneity and transitivity.OS analysis revealed that patients who underwent stereotactic body radiotherapy(SBRT)after resection had longer OS than those who underwent intensity modulated radiotherapy(IMRT)or 3-dimensional conformal RT(3D-CRT).DFS analysis revealed that patients who underwent 3D-CRT after resection had the longest DFS.Patients who underwent IMRT after resection had longer OS than those who underwent 3D-CRT and longer DFS than those who underwent SBRT.CONCLUSION HCC patients who undergo liver cancer resection must consider distinct advantages and disadvantages when choosing between SBRT and 3D-CRT.IMRT,a RT technique that is associated with longer OS than 3D-CRT and longer DFS than SBRT,may be a preferred option.展开更多
The aim of this study was to investigate the feasibility and safety of high-intensity focused ultrasound （HIFU） combined with （＋） low-dose external beam radiotherapy （LRT） as supplemental therapy for advanced p...The aim of this study was to investigate the feasibility and safety of high-intensity focused ultrasound （HIFU） combined with （＋） low-dose external beam radiotherapy （LRT） as supplemental therapy for advanced prostate cancer （PCa） following hormonal therapy （HT）. Our definition of HIFU＋LRT refers to treating primary tumour lesions with HIFU in place of reduced field boost irradiation to the prostate, while retaining four-field box irradiation to the pelvis in conventional-dose external beam radiotherapy （CRT）. We performed a prospective, controlled and non-randomized study on 120 patients with advanced PCa after HT who received HIFU, CRT, HIFU＋LRT and HT alone, respectively. CT/MR imaging showed the primary tumours and pelvic lymph node metastases visibly shrank or even disappeared after HIFU ＋LRT treatment. There were significant differences among four groups with regard to overall survival （OS） and disease-specific survival （DSS） curves （P=0.018 and 0.015）. Further comparison between each pair of groups suggested that the long-term DSS of the H IFU ＋ LRT group was higher than those of the other three groups, but there was no significant difference between the HIFU＋LRT group and the CRT group. Multivariable Cox＇s proportional hazard model showed that both HIFU＋LRT and CRT were independently associated with DSS （P=0.001 and 0.035） and had protective effects with regard to the risk of death. Compared with CRT, HIFU ＋LRT significantly decreased incidences of radiation-related late gastrointestinal （GI） and genitourinary （GU） toxicity grade ≥ II. In conclusion, long-term survival of patients with advanced PCa benefited from strengthening local control of primary tumour and reRional lymph node metastases after HT. As an alternative to CRT, HIFU＋LRT showed Rood efficacy and better safety.展开更多
Objective:To retrospectively investigate the treatment outcomes of external beam radiotherapy with androgen deprivation therapy(ADT)in high-risk prostate cancer in three radiotherapy dose groups.Methods:Between 1998 a...Objective:To retrospectively investigate the treatment outcomes of external beam radiotherapy with androgen deprivation therapy(ADT)in high-risk prostate cancer in three radiotherapy dose groups.Methods:Between 1998 and 2013,patients with high-risk prostate cancer underwent threedimensional conformal radiotherapy or intensity-modulated radiotherapy of 66 Gy,72 Gy,or 78 Gy with ADT.Prostate-specific antigen(PSA)relapse was defined using the Phoenix definition.PSA relapse-free survival(PRFS)was evaluated in each radiotherapy dose group.Moreover,high-risk patients were divided into H-1(patients with multiple high-risk factors)and H-2(patients with a single high-risk factor)as risk subgroups.Results:Two hundred and eighty-nine patients with a median follow-up period of 77.3 months were analyzed in this study.The median duration of ADT was 10.1 months.Age,Gleason score,T stage,and radiotherapy dose influenced PRFS with statistical significance both in univariate and multivariate analyses.The 4-year PRFS rates in Group-66 Gy,Group-72 Gy and Group-78 Gy were 72.7%,81.6%and 90.3%,respectively.PRFS rates in the H-1 subgroup differed with statistical significance with an increasing radiotherapy dose having a more favorable PRFS,while PRFS rates in H-2 subgroup did not differ with increase in radiotherapy dose.Conclusion:Dose escalation for high-risk prostate cancer in combination with ADT improved PRFS.PRFS for patients in the H-1 subgroup was poor,but dose escalation in those patients was beneficial,while dose escalation in the H-2 subgroup was not proven to be effective for improving PRFS.展开更多
Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) ...Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) treatment of cervical cancer. Materials and Methods: A study of QA verification of target doses of 198 cervical cancer patients undergoing External Beam Radiotherapy (EBRT) treatments at two different cancer treatment centers in Kenya was conducted. The target doses were determined from measured entrance doses by the diode in vivo dosimetry. Process Behavior Charts (PBC) developed by SPC were applied for setting Action Thresholds (AT) on the target doses. The AT set was then proposed as QA limits for acceptance or rejection of verified target doses overtime of the EBRT process. Result and Discussion: Target doses for the 198 patients were calculated and SPC applied to test whether the action limits set by the Process Behavior Charts could be applied as QA for verified doses in EBRT. Results for the two sub-groups of n = 3 and n = 4 that were tested produced action thresholds which are within clinical dose specifications for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. Conclusion: Action thresholds set by SPC were within the clinical dose specification of ±5% uncertainty for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. So the concept of SPC could be applied in setting QA action limits for dose verifications in EBRT.展开更多
Objective: Tumours originating from jugular bulb, carotid bifurcation, Vagus nerve are collectively called Paragangliomas. They are slow growing, essentially benign tumours, but can be detrimental if untreated. There ...Objective: Tumours originating from jugular bulb, carotid bifurcation, Vagus nerve are collectively called Paragangliomas. They are slow growing, essentially benign tumours, but can be detrimental if untreated. There is limited evidence on the effectiveness of fractionated radiotherapy in the management ofs Glomus jugulare tumours. The aim of this study is to determine the efficacy of Linear accelerator based fractionated external beam radiotherapy on unilateral inoperable Glomus jugulare paragangliomas. Method: This is a retrospective analysis of all the 12 cases of inoperable, unilateral Glomus jugulare tumours treated during the period 2011-2016 at a tertiary cancer centre in Kenya. Minimum follow up duration was 3 years. Patient characteristics, disease staging, immediate complications and therapeutic efficacy were analysed from the case files. Results: The 12 patients diagnosed with inoperable Glomus jugulare tumours reported in this period were treated with external beam radiotherapy to a tumour dose of 54 Gy in 30 fractions over a period of 6 weeks using IMRT technique in 6 MV Linear accelerator. 2/3<sup>rd </sup>of the patients were females in 5<sup>th</sup> and 6<sup>th</sup> decade of life. Onset of first symptom to initiation of treatment was found to be 1.7 years. Headache, earache, and tinnitus were the main complaints. No major side effects were recorded during therapy. Mean length of the tumour in its maximum dimension at the time of diagnosis was 4.5 cm. At the end of one-year post therapy, a mean reduction of 6.5 mm in the tumour length was observed, (Range: 0 - 15 mm). Tumour size remained static for a year and thereafter a slow growth pattern of 1mm per year was observed. Conclusion: Fractionated external beam radiotherapy is an effective and non-invasive treatment for advanced, inoperable Glomus jugulare paragangliomas. Clinical stability through tumour control was observed. Though newer radiation techniques like Cyberknife, Proton therapy offer better tumour control, conventional external beam radiotherapy is an effective tool in disease containment in resource limited countries.展开更多
Background:To assess the efficacy of metastasis-directed external beam radiotherapy(MDT)in patients with castration-resistant prostate cancer(CRPC),we conducted a multicenter retrospective study.Materials and methods:...Background:To assess the efficacy of metastasis-directed external beam radiotherapy(MDT)in patients with castration-resistant prostate cancer(CRPC),we conducted a multicenter retrospective study.Materials and methods:We retrospectively analyzed data from patients with metastatic CRPC treated with MDT between January 2013 and July 2023 across 14 hospitals.Patients who received palliative or local radiation therapy or had insufficient clinical data were ex-cluded.The primary endpoint was the change in prostate-specific antigen(PSA)levels from pre-to post-MDT.Secondary endpoints included overall survival,time to next systemic therapy,PSA progression-free survival,and reduction of target lesions assessed radiographically.Results:Among 579 patients with metastatic prostate cancer who received radiation therapy,48 underwent MDT.The median follow-up period was 325 days,and the median patient age was 74 years.Metastasis-directed external beam radiotherapy target sites in-cluded bone(n=34,70.8%),lymph nodes(n=11,22.9%),local recurrence(n=2,4.2%),and other sites(n=1,2.1%).Of the 48 pa-tients,30(62.5%)showed a decrease in PSA levels after MDT,and 20(41.6%)achieved a PSA reduction greater than 50%.Among the 26 patients who underwent post-MDT radiographic evaluation,11(42.3%)demonstrated a reduction in target lesions.Median overall survival,PSA progression-free survival,and time to next systemic therapy for patients with and without a PSA response were 1307 ver-sus 614 days(p=0.038,log-rank test),233 versus 98 days(p=0.014,log-rank test),and 434 versus 450 days(p=0.273,log-rank test),respectively.The median PSA doubling time was 4.1 months in PSA responders and 1.7 months in nonresponders.Conclusions:Metastasis-directed external beam radiotherapy resulted in PSA reduction in 62.5%of patients with metastatic CRPC.Metastasis-directed external beam radiotherapy may be a suitable treatment option for patients with a favorable prognosis but may not benefit those with a poor prognosis and short PSA doubling time.展开更多
Gafchromic external beam therapy 3(EBT3)film has widely been used in medical field applications.Principally,the EBT3 film’s color gradually changes from light green to darker color under incremental exposures by ioni...Gafchromic external beam therapy 3(EBT3)film has widely been used in medical field applications.Principally,the EBT3 film’s color gradually changes from light green to darker color under incremental exposures by ionizing or even non-ionizing ultraviolet(UV)radiation.Peak absorbance of the EBT3 film can be used to predict absorbed doses by the film.However,until today,related researches still rely on spectrometers for color analysis of EBT3 films.Hence,this paper presents a comparative analysis between results produced by the spectrometer and a much simpler light-emitting diode-photodiode based system in profiling the color changes of EBT3 films after exposure by solar UV radiation.This work has been conducted on a set of 50 EBT3 samples with incremental solar UV exposure(doses).The wavelength in the red region has the best sensitivity in profiling the color changes of EBT3 films for low solar UV exposure measurement.This study foresees the ability of blue wavelength to profile films with a large range of solar UV exposure.The LED(light emitting diode)-based optical system has produced comparable measurement accuracies to the spectrometer and thus,with a potential for replacing the need for a multipurpose spectroscopy system for simple measurement of light attenuation.展开更多
<strong>Introduction:</strong> <span style="font-family:""><span style="font-family:Verdana;">External-beam radiation therapy boost is a treatment option in cervical ca...<strong>Introduction:</strong> <span style="font-family:""><span style="font-family:Verdana;">External-beam radiation therapy boost is a treatment option in cervical cancer when brachytherapy is not feasible. Though less effective than brachytherapy, some encouraging results have been reported from some institutions experiences. We conducted this study to assess outcomes of EBRT boost for our patients at National Institute of Oncology in Rabat. </span><b><span style="font-family:Verdana;">Patients and Methods: </span></b><span style="font-family:Verdana;">We collected data from patients treated for cervical cancer between January 2012 and December 2015. Patients, tumor and treatment characteristics were collected. Overall survival (OS), disease-free survival (DFS) and prognostic factors influencing DFS were assessed. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> One hundred and thirty-three patients were enrolled. Median age was 52 years. Patient haemoglobin level ranged from 3.9 to 15.5</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">g/dl [mean: 11.2 g/dl]. Most tumors were classified stage III/IVA (63.2%) according to the FIGO classification. Regional lymph node metastases (pelvic and or para-aortic) were observed in 45.1%. Median total dose to tumor was 69.6 Gy (ranging from 66 to 70 Gy). Overall treatment time was protracted, with a median of 60 days. Most of patients received concurrent chemotherapy (94.7%) and the number of cycle ranged from 2 to 7 (median</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">5). The follow-up median was 31.3 months, ranging from 6.2 to 96.8 months. At the first visit, most patients achieved complete response (80.5%). Five years OS and DFS were 47% and 44% respectively. In univariate and multivariate analysis, regional lymph nodes metastasis (presence or absence) and haemoglobin level (≤11</span><span style="font-family:""> </span><span style="font-family:Verdana;">g/dl and >11</span><span style="font-family:""> </span><span style="font-family:Verdana;">g/dl) were the two significant and independent prognostic factors influencing DFS (HR: 1.86;p</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.01 for the former) (HR: 0.59;p</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">0.03 for the latter). </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">Our study showed that EBRT boost in conventional fractionation was an acceptable treatment option for cervical cancer unamenable to brachytherapy, especially in the two subgroups of patients that are those without pelvic and/or para-aortic lymph node metastasis and those with haemoglobin level above 11 g/dl.</span></span>展开更多
A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase w...A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase with the increase in the prestressing force at the tensioning stage, and the natural frequencies decrease after the cracks occur in the beams. Following the calculation formula of natural frequency of externally prestressed beam, which was reported in a literature, the natural frequencies of the experimental beams are calculated, and big errors are found between the test results and the calculated ones of natural frequency values. As a result, this paper has tried to adopt two methods to correct the rigidity parameter of the concrete beam in the formula for natural frequency calculation, and to use the corrected formula to calculate the frequencies of the experimental beams. The calculation results indicate a good consistency with the experimental ones, which verifies the feasibility of the corrected formula.展开更多
Analyses and computations of the natural frequencies of external prestressed concrete structures are the bases for studying the dynamic properties of such structures. We carded out dynamic tests on three types of exte...Analyses and computations of the natural frequencies of external prestressed concrete structures are the bases for studying the dynamic properties of such structures. We carded out dynamic tests on three types of external simply supported beams, pulling the beams gradually. Then vertical loads were applied to the beams while the frequencies and related coefficients were measured at every step. We calculated natural frequencies and the results indicate that natural frequencies increase as the prestressing force rises in the pre-crack stage, and decrease significantly during the post-crack stage. Substantial incoincidences exist between the calculated and experimental results for the frequency and its tendency to changel Based on the experimental results, we modified the stiffness and other parameters in the equations. The results calculated using the modified equations agree with experimental results well, so the modified eauations can be used nractically.展开更多
Background:Radical prostatectomy has long been the treatment of choice for men with clinically significant prostate cancer(PCa)in those with concurrent significant lower urinary tract symptoms(LUTS).For men who meet t...Background:Radical prostatectomy has long been the treatment of choice for men with clinically significant prostate cancer(PCa)in those with concurrent significant lower urinary tract symptoms(LUTS).For men who meet this description with marked prostatomegaly,we present a multi-institutional proof of concept study describing an alternative pathway of robotic simple prostatectomy(RASP)followed by external beam radiation therapy(EBRT)for the treatment of clinically significant prostate cancer.Methods:A retrospective study was performed of 17 patients with PCa who underwent RASP followed by EBRT at two institutions from 2015–2023.Demographic,peri-operative,and post-radiation treatment functional outcomes are reported.Results:No postoperative or post-EBRT complications were reported for any of the 17 patients who underwent RASP followed by EBRT during a median follow-up time of 12 months.The median time from RASP to EBRT was 9 months.Median prostate size was 135 g(IQR 110–165).13(76.5%)patients received a pre-EBRT rectal spacer.Median IPSS score preoperatively improved at 90 days post-RASP(13.5 vs.2.5;IQR 10.8–15.2),and this benefit was sustained post-EBRT with a median IPSS at 3 vs.12 months(4 vs.0;IQR 0–5).There was no statistically significant difference between postoperative IPSS and post-EBRT IPSS at 3(p=0.677)or 12(p=0.627)months.In all 14 patients with localized disease and PSA data,none had recurrence during the study period.Conclusions:A subset of patients with clinically significant prostate cancer have marked prostatomegaly and LUTS.We report an alternative treatment approach for patients unwilling to undergo radical prostatectomy.We found robotic simple prostatectomy followed by definitive radiation to be feasible and safe.展开更多
This paper investigates a highly efficient and promising control method for forced vibration control of an axially moving beam with an attached nonlinear energy sink（NES）.Because of the axial velocity,external force...This paper investigates a highly efficient and promising control method for forced vibration control of an axially moving beam with an attached nonlinear energy sink（NES）.Because of the axial velocity,external force and external excitation frequency,the beam undergoes a high-amplitude vibration.The Galerkin method is applied to discretize the dynamic equations of the beam–NES system.The steady-state responses of the beams with an attached NES and with nothing attached are acquired by numerical simulation.Furthermore,the fast Fourier transform（FFT）is applied to get the amplitude–frequency responses.From the perspective of frequency domain analysis,it is explained that the NES has little effect on the natural frequency of the beam.Results confirm that NES has a great potential to control the excessive vibration.展开更多
Objective： Conventional external beam irradiation techniques for nasopharyngeal carcinoma have limitations, and improving external beam irradiation techniques is needed to enhance the curative rate. This study was de...Objective： Conventional external beam irradiation techniques for nasopharyngeal carcinoma have limitations, and improving external beam irradiation techniques is needed to enhance the curative rate. This study was designed to cvaluate the difference in dose distribution of three dimensional conformal radiotherapy （3D CRT） and conventional treatment plan in early untreated nasopharyngeal carcinoma using a three dimensional treatment planning system. Methods： Twenty-two patients with early untreated nasopharyngeal carcinoma were selected. Conventional and 3D CRT plans were made for each of them and compared with respect to target volume coverage （V95）,normal tissue sparing （D50, D33 and D5, etc）, normal tissue complication probability （NTCP）. Results： The average volumetric dose comparison indicated that the V95 of PTVnx70 were 98.22% and 99.99% （P=0.06）, and PTVnd60, 98.41% and 99.63% （P=1.00）, PTV,x60, 98.44% and 99.98% （P=0.03）, PTVnx50, 98.85% and 99.63% （P=0.02） in conventional and 3DCRT treatment plans respectively. With respect to normal tissue sparing, the average D50 of unilateral parotid glands were 51.91 Gy and 64.30 Gy （P=0.00） respectively, and the unilateral temporomandibular joints, 49.98 Gy and 64.47 Gy （P=0.00）, the Dlcc of spinal cords, 44.98 Gy and 48.09 Gy （P=0.00） in 3D CRT and conventional plans. Conclusion： Though only a little bit better dose coverage of target volume in subclinical lesion region was reached in 3D CRT plans, it spared more normal tissues e.g. parotid glands and temporomandibular joints etc and decreased their NTCP while it got the similar dose distribution in target volumes as conventional plans did for these early nasopharyngeal carcinoma cases.展开更多
Liver transplantation (LT) for hepatocellular carcinoma (HCC) within Milan criteria is a widely accepted optimal therapy. Neo-adjuvant therapy before transplantation has been used as a bridging therapy to prevent drop...Liver transplantation (LT) for hepatocellular carcinoma (HCC) within Milan criteria is a widely accepted optimal therapy. Neo-adjuvant therapy before transplantation has been used as a bridging therapy to prevent dropout during the waiting period and as a down-staging method for the patient with intermediate HCC to qualify for liver transplantation. Transarterial chemoembolization and radiofrequency ablation are the most commonly used method for locoregional therapy. The data associated with newer modalities including drug-eluting beads, radioembolization with Y90, stereotactic radiation therapy and sorafenib will be discussed as a tool for converting advanced HCC to LT candidates. The concept “ablate and wait” has gained the popularity where mandated observation period after neo-adjuvant therapy allows for tumor biology to become apparent, thus has been recommended after down-staging. The role of neo-adjuvant therapy with conjunction of “ablate and wait” in living donor liver transplantation for intermediate stage HCC is also discussed in the paper.展开更多
Bone metastases are rare in primary hepatocellular carcinoma （HCC）. Spinal cord compression （SCC） due to bone metastases occur commonly in patients with lung and breast carcinomas, and metastatic HCC is an unusual...Bone metastases are rare in primary hepatocellular carcinoma （HCC）. Spinal cord compression （SCC） due to bone metastases occur commonly in patients with lung and breast carcinomas, and metastatic HCC is an unusual cause of SCC. Spinal cord compression is an oncologic emergency and treatment delays can lead to irreversible consequences. Thus, the awareness that SCC could be a potential complication of bone metastases due to HCC is of significance in initiation of early treatment that can improve the quality of life and survival of the patients, if diagnosed earlier. This paper describes four cases of primary HCC with varied manifestations of SCC due to bone metastases. The first patient presented primarily with the symptoms of bone pains corresponding to the bone metastases sites rather than symptoms of associated hepatic pathology and eventually developed SCC. The second patient, diagnosed as having HCC, developed extradural SCC leading to paraplegia during the course of illness, for which he underwent emergency laminectomy with posterior fixation. The third patient developed SCC soon after the primary diagnosis and had to undergo emergency laminectomy. Post laminectomy he had good neurological recovery. The Fourth patient presented primarily with radicular pains rather than frank paraplegia as the first manifestation of SCC.展开更多
BACKGROUND In recent years,intraoperative radiotherapy(IORT)has been increasingly used for the treatment of rectal cancer.However,the efficacy and safety of IORT for the treatment of rectal cancer are still controvers...BACKGROUND In recent years,intraoperative radiotherapy(IORT)has been increasingly used for the treatment of rectal cancer.However,the efficacy and safety of IORT for the treatment of rectal cancer are still controversial.AIM To evaluate the value of IORT for patients with rectal cancer.METHODS We searched PubMed,Embase,Cochrane Library,Web of Science databases,and conference abstracts and included randomized controlled trials and observational studies on IORT vs non-IORT for rectal cancer.Dichotomous variables were evaluated by odds ratio(OR)and 95%confidence interval(CI),hazard ratio(HR)and 95%CI was used as a summary statistic of survival outcomes.Statistical analyses were performed using Stata V.15.0 and Review Manager 5.3 software.RESULTS In this study,3 randomized controlled studies and 12 observational studies were included with a total of 1460 patients,who are mainly residents of Europe,the United States,and Asia.Our results did not show significant differences in 5-year overall survival(HR=0.80,95%CI=0.60-1.06;P=0.126);5-year disease-free survival(HR=0.94,95%CI=0.73-1.22;P=0.650);abscess(OR=1.10,95%CI=0.67-1.80;P=0.713),fistulae(OR=0.79,95%CI=0.33-1.89;P=0.600);wound complication(OR=1.21,95%CI=0.62-2.36;P=0.575);anastomotic leakage(OR=1.09,95%CI=0.59-2.02;P=0.775);and neurogenic bladder dysfunction(OR=0.69,95%CI=0.31-1.55;P=0.369).However,the meta-analysis of 5-year local control was significantly different(OR=3.07,95%CI=1.66-5.66;P=0.000).CONCLUSION The advantage of IORT is mainly reflected in 5-year local control,but it is not statistically significant for 5-year overall survival,5-year disease-free survival,and complications.展开更多
Objective： To analyze the treatment results of primary nasopharyngeal carcinoma （NPC） treated in our institution in the beginning of the 21st century to identify key failures and late effects for refining future tr...Objective： To analyze the treatment results of primary nasopharyngeal carcinoma （NPC） treated in our institution in the beginning of the 21st century to identify key failures and late effects for refining future treatments. Methods： 1093 patients with primary NPC treated during December 2001 and June 2003 were retrospectively analyzed. The distribution according to the AJCC/UICC （2002 edition） staging system was stage Ⅰ in 5.8%, stage Ⅱ 40.2%, stage Ⅲ 32.7% and stage Ⅳa-b 21.3%. Four different ERT techniques were used： fluoroscopy simulation conventional radiotherapy （CR） in 74.3% of patients, computer tomography simulation conventional radiotherapy （CT-sim CR） 14.2%, three-dimensional conformal radiotherapy （3D-CRT） 6.3%, intensity modulated radiotherapy （IMRT） 5.2%. In the whole series, 46.7% of patients had additional treatment with chemotherapy. Results： The 4-year local failure-free rate （LFFR）, nodal failure-free rate, distant metastasis-free rate, progression-free survival and overall survival （OS） was 89.6%, 96.1%, 85.9%, 73.0% and 82.4%, respectively. The stage was the most important prognostic factor. The 4-year OS and LFFR of patients treated by CR, CT-sim CR, 3D-CRT and IMRT was 80.2%, 89.8%, 89.8%, 92.4% and 87.7%, 96.4%, 91.0%, 96.5%, respectively. The morbidity and degree of xerostomia and trismus were lower in the patients treated by 3D-CRT and IMRT than by CR and CT-sim CR. Conclusion： Treatment results of primary NPC in our institution have been substantially improved. Distant metastasis is the main failure. The CT simulation and conformal radiotherapy can enhance the OS and LFFR, and conformal radiotherapy can reduce the morbidity and degree of late effects.展开更多
Objective： To report the comparative effect of combined medroxyprogesterone acetate （MPA） and external beam pelvic radiotherapy （EBRT） with EBRT alone on local or distant recurrences, overall survival and treatme...Objective： To report the comparative effect of combined medroxyprogesterone acetate （MPA） and external beam pelvic radiotherapy （EBRT） with EBRT alone on local or distant recurrences, overall survival and treatment related toxicities in patients with stage Ic grade 3 endometrial cancer. Methods： A retrospective review of 80 International Federation of Gyne- cology and Obstetrics （FIGO） stage Ic grade 3 endometrial carcinoma patients treated between October 1994 and October 2004 at Renmin Hospital, Wuhan University, China was performed. All patients underwent surgery, of which 40 patients in arm I received combined MPA and EBRT while in arm II 40 patients received only adjuvant EBRT after surgery. The median dose of EBRT in arm I was 50 Gy （range 36-54 Gy） and in arm Ⅱ was 45.2 Gy （range 43.2-50.4 Gy）. Multivariate analysis was performed for the prognostic factors and Kaplan-Meier method was used for overall survival. Results： Of the 80 eligible patients, 40 in each group could be evaluated. The follow-up times ranged from 4-98 months with a median of 45 months. The overall survival rates at five years were 73% among patients treated with combined MPA and EBRT and 28.2% among patients treated with EBRT alone （P 〈 0.001）. The rate of distant metastasis was significantly higher among patients treated with EBRT alone group than combined MPA and EBRT （55% vs 25%, P = 0.006） while no difference in Ioco regional recurrence rates was observed in both treatment groups. Most of the side effects observed in the combined MPA and EBRT group. Age （P 〈 0.001） and the presence of progesterone receptors （P = 0.003） were independent significant prognostic factors for overall surviva} in multiple regression analysis. Conclusion： We has been concluded that the addition of progestagen to external beam pelvic radiotherapy significantly improved survival and reduced distant metastasis among women with stage Ic grade 3 endometrial cancer.展开更多
Objective This work aims to verify and improve the dose given for cancer patients in radiation therapy by using diodes to enhance patient in vivo dosimetry on a routine basis. Some characteristics of two available sem...Objective This work aims to verify and improve the dose given for cancer patients in radiation therapy by using diodes to enhance patient in vivo dosimetry on a routine basis. Some characteristics of two available semi-conductor diode dosimetry systems were evaluated. Methods The diodes had been calibrated to read the dose at Dmax below the surface. Correction factors of clinical relevance were quantified to convert the diode readings into patient dose. The diode was irradiated at various gantry angles （increments of 45~）, various Field Sizes and various Source to Surface Distances （SSDs）. Results The maximal response variation in the angular response with respect to an arbitrary angle of 0~ was 1.9%, and the minimum variation was 0.5%. The response of the diode with respect to various field siz- es showed the minimum and the maximum variations in the measured dose from the diode; the calculated doses were -1.6% （for 5 cm x 5 cm field size） and 6.6% （for 40 cm x 40 cm field size）. The diode exhibited a significant perturbation in the response, which decreased with increasing SSD. No discrepancies larger than 5% were detected between the expected dose and the measured dose. Conclusion The results indicate that the diodes exhibit excellent linearity, dose reproducibility and minimal anisotropy; that they can be used with confidence for patient dose verification. Furthermore, diodes render real time verification of the dose delivered to patients.展开更多
Objective The aim of the study was to evaluate the efficiency of salvage treatments for prostate specific antigen(PSA)relapse of cT3N0M0 prostatic adenocarcinoma(PCa)after radical prostatectomy(RP)combined with neoadj...Objective The aim of the study was to evaluate the efficiency of salvage treatments for prostate specific antigen(PSA)relapse of cT3N0M0 prostatic adenocarcinoma(PCa)after radical prostatectomy(RP)combined with neoadjuvant androgen deprivation(ADT).Methods A total of 332 patients with cT3N0M0 PCa were enrolled in the prospective study and received RP and pelvic lymph node dissection with neoadjuvant ADT for 3 months.All patients with PSA relapse were treated with salvage external beam radiation therapy(RT)and ADT for 6 months.Results The 5-year postoperative PSA relapse rate was 40.96%(136/332).The patients have been divided into the PSA relapse and PSA relapse-free groups in order to compare patient characteristics.The ratio of patients with Gleason score≥8 and positive surgical margin in the PSA relapse group were significantly higher than those of in the PSA relapse-free group(P=0.01).The mean duration between the start of operative treatment and PSA relapse was 31 months.Salvage treatment to all 136 PSA relapse patients led to favorable outcomes.PSA relapse was not observed after salvage treatment by the end of follow-up.The 5-year overall survival rates of the PSA relapse and PSA relapse-free groups were 94.9%and 93.9%,respectively.Conclusion In pursuit of curative treatment,our study showed that RP combined with neoadjuvant ADT is an aggressive multimodality strategy associated with lower PSA relapse and better survival outcomes for stage cT3N0M0 PCa patients.Patients with PSA relapse after RP may benefit from early aggressive salvage RT combined with short-term ADT.展开更多
基金Supported by The Science and Technology Plan Project of Guangzhou,No.202102010171National Natural Science Foundation。
文摘BACKGROUND Primary liver cancer is a malignant tumor with a high recurrence rate that significantly affects patient prognosis.Postoperative adjuvant external radiation therapy(RT)has been shown to effectively prevent recurrence after liver cancer resection.However,there are multiple RT techniques available,and the differ-ential effects of these techniques in preventing postoperative liver cancer re-currence require further investigation.AIM To assess the advantages and disadvantages of various adjuvant external RT methods after liver resection based on overall survival(OS)and disease-free survival(DFS)and to determine the optimal strategy.METHODS This study involved network meta-analyses and followed the PRISMA guidelines.The data of qualified studies published before July 10,2023,were collected from PubMed,Embase,the Web of Science,and the Cochrane Library.We included relevant studies on postoperative external beam RT after liver resection that had OS and DFS as the primary endpoints.The magnitudes of the effects were determined using risk ratios with 95%confidential intervals.The results were analyzed using R software and STATA software.RESULTS A total of 12 studies,including 1265 patients with hepatocellular carcinoma(HCC)after liver resection,were included in this study.There was no significant heterogeneity in the direct paired comparisons,and there were no significant differences in the inclusion or exclusion criteria,intervention measures,or outcome indicators,meeting the assumptions of heterogeneity and transitivity.OS analysis revealed that patients who underwent stereotactic body radiotherapy(SBRT)after resection had longer OS than those who underwent intensity modulated radiotherapy(IMRT)or 3-dimensional conformal RT(3D-CRT).DFS analysis revealed that patients who underwent 3D-CRT after resection had the longest DFS.Patients who underwent IMRT after resection had longer OS than those who underwent 3D-CRT and longer DFS than those who underwent SBRT.CONCLUSION HCC patients who undergo liver cancer resection must consider distinct advantages and disadvantages when choosing between SBRT and 3D-CRT.IMRT,a RT technique that is associated with longer OS than 3D-CRT and longer DFS than SBRT,may be a preferred option.
文摘The aim of this study was to investigate the feasibility and safety of high-intensity focused ultrasound （HIFU） combined with （＋） low-dose external beam radiotherapy （LRT） as supplemental therapy for advanced prostate cancer （PCa） following hormonal therapy （HT）. Our definition of HIFU＋LRT refers to treating primary tumour lesions with HIFU in place of reduced field boost irradiation to the prostate, while retaining four-field box irradiation to the pelvis in conventional-dose external beam radiotherapy （CRT）. We performed a prospective, controlled and non-randomized study on 120 patients with advanced PCa after HT who received HIFU, CRT, HIFU＋LRT and HT alone, respectively. CT/MR imaging showed the primary tumours and pelvic lymph node metastases visibly shrank or even disappeared after HIFU ＋LRT treatment. There were significant differences among four groups with regard to overall survival （OS） and disease-specific survival （DSS） curves （P=0.018 and 0.015）. Further comparison between each pair of groups suggested that the long-term DSS of the H IFU ＋ LRT group was higher than those of the other three groups, but there was no significant difference between the HIFU＋LRT group and the CRT group. Multivariable Cox＇s proportional hazard model showed that both HIFU＋LRT and CRT were independently associated with DSS （P=0.001 and 0.035） and had protective effects with regard to the risk of death. Compared with CRT, HIFU ＋LRT significantly decreased incidences of radiation-related late gastrointestinal （GI） and genitourinary （GU） toxicity grade ≥ II. In conclusion, long-term survival of patients with advanced PCa benefited from strengthening local control of primary tumour and reRional lymph node metastases after HT. As an alternative to CRT, HIFU＋LRT showed Rood efficacy and better safety.
基金This work was supported in part by the Research and Development Fund of the National Cancer Center and by the Practical Research for Innovative Cancer Control from the Japan Agency for Medical Research and Development(AMED)(26-A-18 and 26-A-28).
文摘Objective:To retrospectively investigate the treatment outcomes of external beam radiotherapy with androgen deprivation therapy(ADT)in high-risk prostate cancer in three radiotherapy dose groups.Methods:Between 1998 and 2013,patients with high-risk prostate cancer underwent threedimensional conformal radiotherapy or intensity-modulated radiotherapy of 66 Gy,72 Gy,or 78 Gy with ADT.Prostate-specific antigen(PSA)relapse was defined using the Phoenix definition.PSA relapse-free survival(PRFS)was evaluated in each radiotherapy dose group.Moreover,high-risk patients were divided into H-1(patients with multiple high-risk factors)and H-2(patients with a single high-risk factor)as risk subgroups.Results:Two hundred and eighty-nine patients with a median follow-up period of 77.3 months were analyzed in this study.The median duration of ADT was 10.1 months.Age,Gleason score,T stage,and radiotherapy dose influenced PRFS with statistical significance both in univariate and multivariate analyses.The 4-year PRFS rates in Group-66 Gy,Group-72 Gy and Group-78 Gy were 72.7%,81.6%and 90.3%,respectively.PRFS rates in the H-1 subgroup differed with statistical significance with an increasing radiotherapy dose having a more favorable PRFS,while PRFS rates in H-2 subgroup did not differ with increase in radiotherapy dose.Conclusion:Dose escalation for high-risk prostate cancer in combination with ADT improved PRFS.PRFS for patients in the H-1 subgroup was poor,but dose escalation in those patients was beneficial,while dose escalation in the H-2 subgroup was not proven to be effective for improving PRFS.
文摘Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) treatment of cervical cancer. Materials and Methods: A study of QA verification of target doses of 198 cervical cancer patients undergoing External Beam Radiotherapy (EBRT) treatments at two different cancer treatment centers in Kenya was conducted. The target doses were determined from measured entrance doses by the diode in vivo dosimetry. Process Behavior Charts (PBC) developed by SPC were applied for setting Action Thresholds (AT) on the target doses. The AT set was then proposed as QA limits for acceptance or rejection of verified target doses overtime of the EBRT process. Result and Discussion: Target doses for the 198 patients were calculated and SPC applied to test whether the action limits set by the Process Behavior Charts could be applied as QA for verified doses in EBRT. Results for the two sub-groups of n = 3 and n = 4 that were tested produced action thresholds which are within clinical dose specifications for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. Conclusion: Action thresholds set by SPC were within the clinical dose specification of ±5% uncertainty for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. So the concept of SPC could be applied in setting QA action limits for dose verifications in EBRT.
文摘Objective: Tumours originating from jugular bulb, carotid bifurcation, Vagus nerve are collectively called Paragangliomas. They are slow growing, essentially benign tumours, but can be detrimental if untreated. There is limited evidence on the effectiveness of fractionated radiotherapy in the management ofs Glomus jugulare tumours. The aim of this study is to determine the efficacy of Linear accelerator based fractionated external beam radiotherapy on unilateral inoperable Glomus jugulare paragangliomas. Method: This is a retrospective analysis of all the 12 cases of inoperable, unilateral Glomus jugulare tumours treated during the period 2011-2016 at a tertiary cancer centre in Kenya. Minimum follow up duration was 3 years. Patient characteristics, disease staging, immediate complications and therapeutic efficacy were analysed from the case files. Results: The 12 patients diagnosed with inoperable Glomus jugulare tumours reported in this period were treated with external beam radiotherapy to a tumour dose of 54 Gy in 30 fractions over a period of 6 weeks using IMRT technique in 6 MV Linear accelerator. 2/3<sup>rd </sup>of the patients were females in 5<sup>th</sup> and 6<sup>th</sup> decade of life. Onset of first symptom to initiation of treatment was found to be 1.7 years. Headache, earache, and tinnitus were the main complaints. No major side effects were recorded during therapy. Mean length of the tumour in its maximum dimension at the time of diagnosis was 4.5 cm. At the end of one-year post therapy, a mean reduction of 6.5 mm in the tumour length was observed, (Range: 0 - 15 mm). Tumour size remained static for a year and thereafter a slow growth pattern of 1mm per year was observed. Conclusion: Fractionated external beam radiotherapy is an effective and non-invasive treatment for advanced, inoperable Glomus jugulare paragangliomas. Clinical stability through tumour control was observed. Though newer radiation techniques like Cyberknife, Proton therapy offer better tumour control, conventional external beam radiotherapy is an effective tool in disease containment in resource limited countries.
文摘Background:To assess the efficacy of metastasis-directed external beam radiotherapy(MDT)in patients with castration-resistant prostate cancer(CRPC),we conducted a multicenter retrospective study.Materials and methods:We retrospectively analyzed data from patients with metastatic CRPC treated with MDT between January 2013 and July 2023 across 14 hospitals.Patients who received palliative or local radiation therapy or had insufficient clinical data were ex-cluded.The primary endpoint was the change in prostate-specific antigen(PSA)levels from pre-to post-MDT.Secondary endpoints included overall survival,time to next systemic therapy,PSA progression-free survival,and reduction of target lesions assessed radiographically.Results:Among 579 patients with metastatic prostate cancer who received radiation therapy,48 underwent MDT.The median follow-up period was 325 days,and the median patient age was 74 years.Metastasis-directed external beam radiotherapy target sites in-cluded bone(n=34,70.8%),lymph nodes(n=11,22.9%),local recurrence(n=2,4.2%),and other sites(n=1,2.1%).Of the 48 pa-tients,30(62.5%)showed a decrease in PSA levels after MDT,and 20(41.6%)achieved a PSA reduction greater than 50%.Among the 26 patients who underwent post-MDT radiographic evaluation,11(42.3%)demonstrated a reduction in target lesions.Median overall survival,PSA progression-free survival,and time to next systemic therapy for patients with and without a PSA response were 1307 ver-sus 614 days(p=0.038,log-rank test),233 versus 98 days(p=0.014,log-rank test),and 434 versus 450 days(p=0.273,log-rank test),respectively.The median PSA doubling time was 4.1 months in PSA responders and 1.7 months in nonresponders.Conclusions:Metastasis-directed external beam radiotherapy resulted in PSA reduction in 62.5%of patients with metastatic CRPC.Metastasis-directed external beam radiotherapy may be a suitable treatment option for patients with a favorable prognosis but may not benefit those with a poor prognosis and short PSA doubling time.
基金This work was financially supported by the Ministry of Higher Education Malaysia-Fundamental Research Grant Scheme(Grant No.203/PFIZIK/6711491).
文摘Gafchromic external beam therapy 3(EBT3)film has widely been used in medical field applications.Principally,the EBT3 film’s color gradually changes from light green to darker color under incremental exposures by ionizing or even non-ionizing ultraviolet(UV)radiation.Peak absorbance of the EBT3 film can be used to predict absorbed doses by the film.However,until today,related researches still rely on spectrometers for color analysis of EBT3 films.Hence,this paper presents a comparative analysis between results produced by the spectrometer and a much simpler light-emitting diode-photodiode based system in profiling the color changes of EBT3 films after exposure by solar UV radiation.This work has been conducted on a set of 50 EBT3 samples with incremental solar UV exposure(doses).The wavelength in the red region has the best sensitivity in profiling the color changes of EBT3 films for low solar UV exposure measurement.This study foresees the ability of blue wavelength to profile films with a large range of solar UV exposure.The LED(light emitting diode)-based optical system has produced comparable measurement accuracies to the spectrometer and thus,with a potential for replacing the need for a multipurpose spectroscopy system for simple measurement of light attenuation.
文摘<strong>Introduction:</strong> <span style="font-family:""><span style="font-family:Verdana;">External-beam radiation therapy boost is a treatment option in cervical cancer when brachytherapy is not feasible. Though less effective than brachytherapy, some encouraging results have been reported from some institutions experiences. We conducted this study to assess outcomes of EBRT boost for our patients at National Institute of Oncology in Rabat. </span><b><span style="font-family:Verdana;">Patients and Methods: </span></b><span style="font-family:Verdana;">We collected data from patients treated for cervical cancer between January 2012 and December 2015. Patients, tumor and treatment characteristics were collected. Overall survival (OS), disease-free survival (DFS) and prognostic factors influencing DFS were assessed. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> One hundred and thirty-three patients were enrolled. Median age was 52 years. Patient haemoglobin level ranged from 3.9 to 15.5</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">g/dl [mean: 11.2 g/dl]. Most tumors were classified stage III/IVA (63.2%) according to the FIGO classification. Regional lymph node metastases (pelvic and or para-aortic) were observed in 45.1%. Median total dose to tumor was 69.6 Gy (ranging from 66 to 70 Gy). Overall treatment time was protracted, with a median of 60 days. Most of patients received concurrent chemotherapy (94.7%) and the number of cycle ranged from 2 to 7 (median</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">5). The follow-up median was 31.3 months, ranging from 6.2 to 96.8 months. At the first visit, most patients achieved complete response (80.5%). Five years OS and DFS were 47% and 44% respectively. In univariate and multivariate analysis, regional lymph nodes metastasis (presence or absence) and haemoglobin level (≤11</span><span style="font-family:""> </span><span style="font-family:Verdana;">g/dl and >11</span><span style="font-family:""> </span><span style="font-family:Verdana;">g/dl) were the two significant and independent prognostic factors influencing DFS (HR: 1.86;p</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.01 for the former) (HR: 0.59;p</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">0.03 for the latter). </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">Our study showed that EBRT boost in conventional fractionation was an acceptable treatment option for cervical cancer unamenable to brachytherapy, especially in the two subgroups of patients that are those without pelvic and/or para-aortic lymph node metastasis and those with haemoglobin level above 11 g/dl.</span></span>
基金supported by the National Natural Science Foundation of China (No.50808090)
文摘A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase with the increase in the prestressing force at the tensioning stage, and the natural frequencies decrease after the cracks occur in the beams. Following the calculation formula of natural frequency of externally prestressed beam, which was reported in a literature, the natural frequencies of the experimental beams are calculated, and big errors are found between the test results and the calculated ones of natural frequency values. As a result, this paper has tried to adopt two methods to correct the rigidity parameter of the concrete beam in the formula for natural frequency calculation, and to use the corrected formula to calculate the frequencies of the experimental beams. The calculation results indicate a good consistency with the experimental ones, which verifies the feasibility of the corrected formula.
基金Funded by the National Science Foundation of China (No. 50808090)
文摘Analyses and computations of the natural frequencies of external prestressed concrete structures are the bases for studying the dynamic properties of such structures. We carded out dynamic tests on three types of external simply supported beams, pulling the beams gradually. Then vertical loads were applied to the beams while the frequencies and related coefficients were measured at every step. We calculated natural frequencies and the results indicate that natural frequencies increase as the prestressing force rises in the pre-crack stage, and decrease significantly during the post-crack stage. Substantial incoincidences exist between the calculated and experimental results for the frequency and its tendency to changel Based on the experimental results, we modified the stiffness and other parameters in the equations. The results calculated using the modified equations agree with experimental results well, so the modified eauations can be used nractically.
文摘Background:Radical prostatectomy has long been the treatment of choice for men with clinically significant prostate cancer(PCa)in those with concurrent significant lower urinary tract symptoms(LUTS).For men who meet this description with marked prostatomegaly,we present a multi-institutional proof of concept study describing an alternative pathway of robotic simple prostatectomy(RASP)followed by external beam radiation therapy(EBRT)for the treatment of clinically significant prostate cancer.Methods:A retrospective study was performed of 17 patients with PCa who underwent RASP followed by EBRT at two institutions from 2015–2023.Demographic,peri-operative,and post-radiation treatment functional outcomes are reported.Results:No postoperative or post-EBRT complications were reported for any of the 17 patients who underwent RASP followed by EBRT during a median follow-up time of 12 months.The median time from RASP to EBRT was 9 months.Median prostate size was 135 g(IQR 110–165).13(76.5%)patients received a pre-EBRT rectal spacer.Median IPSS score preoperatively improved at 90 days post-RASP(13.5 vs.2.5;IQR 10.8–15.2),and this benefit was sustained post-EBRT with a median IPSS at 3 vs.12 months(4 vs.0;IQR 0–5).There was no statistically significant difference between postoperative IPSS and post-EBRT IPSS at 3(p=0.677)or 12(p=0.627)months.In all 14 patients with localized disease and PSA data,none had recurrence during the study period.Conclusions:A subset of patients with clinically significant prostate cancer have marked prostatomegaly and LUTS.We report an alternative treatment approach for patients unwilling to undergo radical prostatectomy.We found robotic simple prostatectomy followed by definitive radiation to be feasible and safe.
基金supported by the National Natural Science Foundation of China (project nos.11772205 , 11202140 , 11402151 , 11572182 , 51305421)the funding support from the Natural Science Foundation of Liaoning Province (201501708)
文摘This paper investigates a highly efficient and promising control method for forced vibration control of an axially moving beam with an attached nonlinear energy sink（NES）.Because of the axial velocity,external force and external excitation frequency,the beam undergoes a high-amplitude vibration.The Galerkin method is applied to discretize the dynamic equations of the beam–NES system.The steady-state responses of the beams with an attached NES and with nothing attached are acquired by numerical simulation.Furthermore,the fast Fourier transform（FFT）is applied to get the amplitude–frequency responses.From the perspective of frequency domain analysis,it is explained that the NES has little effect on the natural frequency of the beam.Results confirm that NES has a great potential to control the excessive vibration.
基金This project was supported by a grant from Guangdong Medical Research Foundation (No.Al999214).
文摘Objective： Conventional external beam irradiation techniques for nasopharyngeal carcinoma have limitations, and improving external beam irradiation techniques is needed to enhance the curative rate. This study was designed to cvaluate the difference in dose distribution of three dimensional conformal radiotherapy （3D CRT） and conventional treatment plan in early untreated nasopharyngeal carcinoma using a three dimensional treatment planning system. Methods： Twenty-two patients with early untreated nasopharyngeal carcinoma were selected. Conventional and 3D CRT plans were made for each of them and compared with respect to target volume coverage （V95）,normal tissue sparing （D50, D33 and D5, etc）, normal tissue complication probability （NTCP）. Results： The average volumetric dose comparison indicated that the V95 of PTVnx70 were 98.22% and 99.99% （P=0.06）, and PTVnd60, 98.41% and 99.63% （P=1.00）, PTV,x60, 98.44% and 99.98% （P=0.03）, PTVnx50, 98.85% and 99.63% （P=0.02） in conventional and 3DCRT treatment plans respectively. With respect to normal tissue sparing, the average D50 of unilateral parotid glands were 51.91 Gy and 64.30 Gy （P=0.00） respectively, and the unilateral temporomandibular joints, 49.98 Gy and 64.47 Gy （P=0.00）, the Dlcc of spinal cords, 44.98 Gy and 48.09 Gy （P=0.00） in 3D CRT and conventional plans. Conclusion： Though only a little bit better dose coverage of target volume in subclinical lesion region was reached in 3D CRT plans, it spared more normal tissues e.g. parotid glands and temporomandibular joints etc and decreased their NTCP while it got the similar dose distribution in target volumes as conventional plans did for these early nasopharyngeal carcinoma cases.
文摘Liver transplantation (LT) for hepatocellular carcinoma (HCC) within Milan criteria is a widely accepted optimal therapy. Neo-adjuvant therapy before transplantation has been used as a bridging therapy to prevent dropout during the waiting period and as a down-staging method for the patient with intermediate HCC to qualify for liver transplantation. Transarterial chemoembolization and radiofrequency ablation are the most commonly used method for locoregional therapy. The data associated with newer modalities including drug-eluting beads, radioembolization with Y90, stereotactic radiation therapy and sorafenib will be discussed as a tool for converting advanced HCC to LT candidates. The concept “ablate and wait” has gained the popularity where mandated observation period after neo-adjuvant therapy allows for tumor biology to become apparent, thus has been recommended after down-staging. The role of neo-adjuvant therapy with conjunction of “ablate and wait” in living donor liver transplantation for intermediate stage HCC is also discussed in the paper.
文摘Bone metastases are rare in primary hepatocellular carcinoma （HCC）. Spinal cord compression （SCC） due to bone metastases occur commonly in patients with lung and breast carcinomas, and metastatic HCC is an unusual cause of SCC. Spinal cord compression is an oncologic emergency and treatment delays can lead to irreversible consequences. Thus, the awareness that SCC could be a potential complication of bone metastases due to HCC is of significance in initiation of early treatment that can improve the quality of life and survival of the patients, if diagnosed earlier. This paper describes four cases of primary HCC with varied manifestations of SCC due to bone metastases. The first patient presented primarily with the symptoms of bone pains corresponding to the bone metastases sites rather than symptoms of associated hepatic pathology and eventually developed SCC. The second patient, diagnosed as having HCC, developed extradural SCC leading to paraplegia during the course of illness, for which he underwent emergency laminectomy with posterior fixation. The third patient developed SCC soon after the primary diagnosis and had to undergo emergency laminectomy. Post laminectomy he had good neurological recovery. The Fourth patient presented primarily with radicular pains rather than frank paraplegia as the first manifestation of SCC.
基金Supported by Natural Science Foundation of Gansu Province,China,No.18JR3RA052Gansu Province Da Vinci robot high end diagnosis and treatment personnel training project+2 种基金National Key Research and Development Program Task Book,No.2018YFC1311506Lanzhou Talent Innovation and Entrepreneurship Project Task Contract,No.2016-RC-562019 Graduate Innovation Fund Project,No.2020CX50.
文摘BACKGROUND In recent years,intraoperative radiotherapy(IORT)has been increasingly used for the treatment of rectal cancer.However,the efficacy and safety of IORT for the treatment of rectal cancer are still controversial.AIM To evaluate the value of IORT for patients with rectal cancer.METHODS We searched PubMed,Embase,Cochrane Library,Web of Science databases,and conference abstracts and included randomized controlled trials and observational studies on IORT vs non-IORT for rectal cancer.Dichotomous variables were evaluated by odds ratio(OR)and 95%confidence interval(CI),hazard ratio(HR)and 95%CI was used as a summary statistic of survival outcomes.Statistical analyses were performed using Stata V.15.0 and Review Manager 5.3 software.RESULTS In this study,3 randomized controlled studies and 12 observational studies were included with a total of 1460 patients,who are mainly residents of Europe,the United States,and Asia.Our results did not show significant differences in 5-year overall survival(HR=0.80,95%CI=0.60-1.06;P=0.126);5-year disease-free survival(HR=0.94,95%CI=0.73-1.22;P=0.650);abscess(OR=1.10,95%CI=0.67-1.80;P=0.713),fistulae(OR=0.79,95%CI=0.33-1.89;P=0.600);wound complication(OR=1.21,95%CI=0.62-2.36;P=0.575);anastomotic leakage(OR=1.09,95%CI=0.59-2.02;P=0.775);and neurogenic bladder dysfunction(OR=0.69,95%CI=0.31-1.55;P=0.369).However,the meta-analysis of 5-year local control was significantly different(OR=3.07,95%CI=1.66-5.66;P=0.000).CONCLUSION The advantage of IORT is mainly reflected in 5-year local control,but it is not statistically significant for 5-year overall survival,5-year disease-free survival,and complications.
文摘Objective： To analyze the treatment results of primary nasopharyngeal carcinoma （NPC） treated in our institution in the beginning of the 21st century to identify key failures and late effects for refining future treatments. Methods： 1093 patients with primary NPC treated during December 2001 and June 2003 were retrospectively analyzed. The distribution according to the AJCC/UICC （2002 edition） staging system was stage Ⅰ in 5.8%, stage Ⅱ 40.2%, stage Ⅲ 32.7% and stage Ⅳa-b 21.3%. Four different ERT techniques were used： fluoroscopy simulation conventional radiotherapy （CR） in 74.3% of patients, computer tomography simulation conventional radiotherapy （CT-sim CR） 14.2%, three-dimensional conformal radiotherapy （3D-CRT） 6.3%, intensity modulated radiotherapy （IMRT） 5.2%. In the whole series, 46.7% of patients had additional treatment with chemotherapy. Results： The 4-year local failure-free rate （LFFR）, nodal failure-free rate, distant metastasis-free rate, progression-free survival and overall survival （OS） was 89.6%, 96.1%, 85.9%, 73.0% and 82.4%, respectively. The stage was the most important prognostic factor. The 4-year OS and LFFR of patients treated by CR, CT-sim CR, 3D-CRT and IMRT was 80.2%, 89.8%, 89.8%, 92.4% and 87.7%, 96.4%, 91.0%, 96.5%, respectively. The morbidity and degree of xerostomia and trismus were lower in the patients treated by 3D-CRT and IMRT than by CR and CT-sim CR. Conclusion： Treatment results of primary NPC in our institution have been substantially improved. Distant metastasis is the main failure. The CT simulation and conformal radiotherapy can enhance the OS and LFFR, and conformal radiotherapy can reduce the morbidity and degree of late effects.
文摘Objective： To report the comparative effect of combined medroxyprogesterone acetate （MPA） and external beam pelvic radiotherapy （EBRT） with EBRT alone on local or distant recurrences, overall survival and treatment related toxicities in patients with stage Ic grade 3 endometrial cancer. Methods： A retrospective review of 80 International Federation of Gyne- cology and Obstetrics （FIGO） stage Ic grade 3 endometrial carcinoma patients treated between October 1994 and October 2004 at Renmin Hospital, Wuhan University, China was performed. All patients underwent surgery, of which 40 patients in arm I received combined MPA and EBRT while in arm II 40 patients received only adjuvant EBRT after surgery. The median dose of EBRT in arm I was 50 Gy （range 36-54 Gy） and in arm Ⅱ was 45.2 Gy （range 43.2-50.4 Gy）. Multivariate analysis was performed for the prognostic factors and Kaplan-Meier method was used for overall survival. Results： Of the 80 eligible patients, 40 in each group could be evaluated. The follow-up times ranged from 4-98 months with a median of 45 months. The overall survival rates at five years were 73% among patients treated with combined MPA and EBRT and 28.2% among patients treated with EBRT alone （P 〈 0.001）. The rate of distant metastasis was significantly higher among patients treated with EBRT alone group than combined MPA and EBRT （55% vs 25%, P = 0.006） while no difference in Ioco regional recurrence rates was observed in both treatment groups. Most of the side effects observed in the combined MPA and EBRT group. Age （P 〈 0.001） and the presence of progesterone receptors （P = 0.003） were independent significant prognostic factors for overall surviva} in multiple regression analysis. Conclusion： We has been concluded that the addition of progestagen to external beam pelvic radiotherapy significantly improved survival and reduced distant metastasis among women with stage Ic grade 3 endometrial cancer.
基金Supported by grants from Tanta University and Al-Hosain HospitalFaculty of Medicine+1 种基金Al Azhar UniversityEgypt
文摘Objective This work aims to verify and improve the dose given for cancer patients in radiation therapy by using diodes to enhance patient in vivo dosimetry on a routine basis. Some characteristics of two available semi-conductor diode dosimetry systems were evaluated. Methods The diodes had been calibrated to read the dose at Dmax below the surface. Correction factors of clinical relevance were quantified to convert the diode readings into patient dose. The diode was irradiated at various gantry angles （increments of 45~）, various Field Sizes and various Source to Surface Distances （SSDs）. Results The maximal response variation in the angular response with respect to an arbitrary angle of 0~ was 1.9%, and the minimum variation was 0.5%. The response of the diode with respect to various field siz- es showed the minimum and the maximum variations in the measured dose from the diode; the calculated doses were -1.6% （for 5 cm x 5 cm field size） and 6.6% （for 40 cm x 40 cm field size）. The diode exhibited a significant perturbation in the response, which decreased with increasing SSD. No discrepancies larger than 5% were detected between the expected dose and the measured dose. Conclusion The results indicate that the diodes exhibit excellent linearity, dose reproducibility and minimal anisotropy; that they can be used with confidence for patient dose verification. Furthermore, diodes render real time verification of the dose delivered to patients.
文摘Objective The aim of the study was to evaluate the efficiency of salvage treatments for prostate specific antigen(PSA)relapse of cT3N0M0 prostatic adenocarcinoma(PCa)after radical prostatectomy(RP)combined with neoadjuvant androgen deprivation(ADT).Methods A total of 332 patients with cT3N0M0 PCa were enrolled in the prospective study and received RP and pelvic lymph node dissection with neoadjuvant ADT for 3 months.All patients with PSA relapse were treated with salvage external beam radiation therapy(RT)and ADT for 6 months.Results The 5-year postoperative PSA relapse rate was 40.96%(136/332).The patients have been divided into the PSA relapse and PSA relapse-free groups in order to compare patient characteristics.The ratio of patients with Gleason score≥8 and positive surgical margin in the PSA relapse group were significantly higher than those of in the PSA relapse-free group(P=0.01).The mean duration between the start of operative treatment and PSA relapse was 31 months.Salvage treatment to all 136 PSA relapse patients led to favorable outcomes.PSA relapse was not observed after salvage treatment by the end of follow-up.The 5-year overall survival rates of the PSA relapse and PSA relapse-free groups were 94.9%and 93.9%,respectively.Conclusion In pursuit of curative treatment,our study showed that RP combined with neoadjuvant ADT is an aggressive multimodality strategy associated with lower PSA relapse and better survival outcomes for stage cT3N0M0 PCa patients.Patients with PSA relapse after RP may benefit from early aggressive salvage RT combined with short-term ADT.
