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Objective To analyze the data from intensity-modulated radiotherapy ( IMRT) for prostate cancer guided by kilovoltage cone-beam computed tomography (CBCT), and to provide a clinical basis for selecting the optimal image registration method and reasonable target volume margins.Methods A total of 16 patients with prostate cancer who received radical IMRT were enrolled, and CBCT for online position verification was performed 214 times.The images were obtained after conventional skin marking and laser alignment, and automatic registration, bone registration, soft tissue registration, and manual registration were performed for CBCT images and planned CT images.The differences between these four registration methods were evaluated, and the margins for extending clinical target volume into planning target volume (PTV) were calculated.Results The setup errors in left-right, anterior-posterior, and cranial-caudal directions for automatic registration, bone registration, soft tissue registration, and manual registration were-0.6±2.8 mm/-0.6±4.5 mm/-0.6±3.8 mm,-0.7±2.7 mm/-0.9±4.5 mm/-0.8±4.1 mm,-0.8± 2.6 mm/-0.3±4.4 mm/-1.1±4.0 mm, and-0.6±2.9 mm/-0.7±5.1 mm/-0.9±3.9 mm, respectively. There were no significant differences between the four registration methods.The margins for extension in the left-right, anterior-posterior, and cranial-caudal directions were calculated as 4.7 mm, 5.2 mm, and 6.5 mm, respectively.Conclusions With a comprehensive consideration of various factors, a default setting of automatic registration and manual fine adjustment is appropriate for CBCT-guided radiotherapy for prostate cancer.The margins for extension in the left-right, anterior-posterior, and cranial-caudal directions are 4.7 mm, 5.2 mm, and 6.5 mm, respectively.
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Objective To observe the motions of the rectum and bladder by image?guided radiotherapy ( IGRT) and to analyze their impact on treatment. Methods Eighteen patients with prostate cancer undergoing intensity?modulated radiotherapy ( IMRT) were enrolled in the study and 247 cone?beam computed tomography ( CBCT) images were obtained from this study. The clinical target volume, bladder, and rectum were contoured on all simulated CT and CBCT to examine their volume and position changes. The dose distributions were recalculated based on the data of the x?, y?, and z?axis setup errors. The doses to planning target volume ( PTV) and organs at risk were calculated in the replanning, and their impact on treatment was analyzed. Comparison of the planning and replanning results was made by paired t?test. The effects of displacements and volumes of the bladder and rectum on target doses were analyzed by Pearson correlation method. Results Great changes in the volumes of the bladder and rectum were observed during the treatment. For the planning and replanning results, PTVD95% was 7777. 37 cGy vs. 7628. 56 cGy ( P=0. 027), PTV Dmin was 87. 91 cGy vs. 83. 35 cGy (P=0. 000), and RVP was 5. 89% vs. 8. 31%(P=0. 000). There were correlations between PTVD95% and the motions of the bladder and rectum, with correlation coefficients of 0. 296 and 0. 177, respectively. The correlation coefficient between rectal volume and PTVD95% was 0. 115, indicating a certain correlation. There is a certain correlation between and PTV Dmin and bladder volume, with a correlation coefficient of?0. 128. Conclusions The recovery of the state during localization for the bladder and rectum, especially the latter, has great significance to ensure the target dose and reduce exposure of the rectum in the IMRT for prostate cancer.
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Objective To evaluate the efficacy and tolerance of preoperative concurrent chemoradiotherapy in the treatment of locally advanced middle-low rectal cancer.Methods From June 2007 to June 2013,51 untreated patients with histopathologically proven rectal cancer (T3/T4 or N (+))were included in this study.Three-dimensional radiotherapy was delivered to the whole pelvic cavity at 45.0-50.4 Gy/25-28 fractions.Two cycles of chemotherapy with FOLFOX4 or XELOX were given concurrently at weeks 1 and 4 of radiotherapy.Surgery was performed at 4-8 weeks after chemoradiotherapy.Adjuvant chemotherapy with FOLFOX4 or XELOX was given within one month after surgery.The Kaplan-Meier method was used to calculate survival rates,and the log-rank test was used for univariate analysis;the Cox regression model was used for multivariate prognostic analysis.Results Fortynine patients completed the preoperative chemoradiotherapy and surgery.The median follow-up was 2.9 years.The overall sphincter preservation rate was 65％;the overall downstaging rate was 59％.Ten (20.4％) of all patients achieved a pathologic complete response (pCR).Grade ≥3 toxicities occurred in 25％ of all patients,and the overall postoperative complication rate was 31％.The 3-and 5-year sample sizes were 24,12,respectively.The 3-and 5-year overall survival rates were 81％ and 69％,respectively;the 3-and 5-year disease-free survival (DFS) rates were 76％ and 60％,respectively;the 3-and 5-year local recurrence-free survival (LRFS) rates were 78％ and 70％,respectively;the distant metastasis-free survival rates were 82％ and 74％,respectively.The multivariate analysis showed that tumor downstaging was an independent prognostic factor for 5-year DFS and LRFS.Conclusions For locally advanced middle-low rectal cancer,preoperative radiotherapy with concurrent FOLFOX4/XELOX chemotherapy can increase pathologic downstaging rate,pCR rate,and sphincter preservation rate.Patients with tumor downstaging may have a better survival advantage.
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Objective To meet the special needs of the department of radiation oncology, a radiation therapy information management system ( RTIMS) has been developed as a secondary database system to supplement the Varian Varis/Aria since 2007. Methods The RTIMS server was used to run a database and web service of Apache + PHP + MySQL. The RTIMS sever's web service could be visited with Internet Explorer (IE) to input, search, count, and print informations from about 30 workstations and 20 personal computers. As some workstations were installed with Windows and IE in English only, some functions had English version. Results In past five years, as the RTIMS was implemented in the department, some further needs were met and more practical functions were developed. And now the RTIMS almost covered the whole workflow of radiation therapy ( RT) . By September 2011 , recorded patients data in the RTIMS is as follows: 3900 patients, 2600 0utpatient RT records, 6800 progress notes, 1900 RT summaries, 6700 charge records, 83000 workload records, 3900 plan application forms, 1600 ICRT records. etc. Conclusions The RTIMS hased on the workflow of RT has been successfully developed and clinically implemented. And it was demonstrated to be user-friendly and was proven to significantly improve the efficiency of the department. Since it is an in-house developed system, more functions can be added or modified to further enhance its potentials in research and clinical practice.
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Objective To analyze the prognostic factors of patients with leukemia treated with single fraction total body irradiation (SFTBI) followed by hernatopoietic stem cell transplantation (HSCT).Methods From January 2001 to September 2008, 102 patients received HSCT. The differences of the survival rate, relapse rate and incidence of interstitial pneumonia (IP) between groups regarding different genders, ages, pathological types, transplantation methods and TBI parameters were compared and the factors related with the survival rate, relapse rate and incidence of IP were analyzed. Results The followup time ranged from 15 to 1482 days (median, 406 days). The follow-up rate was 95.1%. 86 and 55patients were followed up more than one year and three years. The 1-and 3-year survival rates were 59.0%and 44.0%. In univariate analysis, the 3-year survival rate was signifcantly different between the groups with and without relapse before transplantation (20% vs. 55%, χ2 = 6.33, P = 0. 012), allogeneictranplantation versus autologous tranplantation (39% vs. 68%, χ2 = 8.06, P = 0.005), grade 3 or more acute graft versus host disease (aGVHD) and grade 0 -2 aGVHD (0% vs. 54%, χ2 = 7.52, P = 0.006),with and without relapse after transplantation (19% vs. 58%, χ2 = 10.13, P =0.001), with and without IP (23% vs. 58%, χ2 =8.35, P=0.004). Multivariate analysis showed that grade 3 or more aGVHD was the only statistically significant prognostic factors (χ2 = 12. 74 ,P =0. 000). The l-and 3-year relapse rateswere 30. 0% and 50. 0%. The incidence of relapse was obviously higher in the group with relapse before transplantation than that without (47% vs. 16%, χ2 =7. 32, P=0. 007). Multivariate analysis showed thatrelapse before transplantation was a significant factor predicting relapse after transplantation (χ2 = 9. 39,P =0. 020). The cumulative incidence of IP was 35.0%. The incidence of IP was different between groups with dose homogeneity > 3% and ≤ 3% (27% vs. 4%, χ2 = 5. 21, P = 0. 023), with and without acute parotitis (34% vs. 3%, χ2 = 14. 15, P= 0.000), allogeneic transplantation group and autologous transplantation group (31% vs. 8%, χ2= 7.70, P= 0.006). Multivariate analysis showed that transplantation methods, acute parotitis and dose homogeneity were statistically significant factors in predictingIP (χ2 = 10. 08 , 10. 08 and 7.69 , P = 0. 002 , 0. 002 and 0. 010 , respectively) . Conclusions Patients who develop grade 3 or higher aGVHD have poor prognosis. Dose homogeneity influences the incidence of IP. Patients undergoing allogeneic transplantation are apt to have IP. Acute parotitis is related with IP and might be a predictor.
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Objective To evaluate the change of myasthenia gravis(MG) during radiotherapy for patients with malignant thymomas.Methods Forty-five with malignant thymomas patients with were analyzed.The median total dose was DT54.2?Gy in 1.8-2.0?Gy /fraction,5 days a week.Anti-cholinesterase,such as pyridostigmine was used to control the MG symptoms.Results Forty-five patients completed radiotherapy on schedule except one from whom the treatment was was with drawn because of respiratory muscle involvement.Among these 44 patients,myasthenic symptom was relieved in 4 to various degrees,4 progressed,34 no change and 2 developed cholinergic crisis.Myasthenic symptom was not changed in one patient for whom radiotherapy had been standed before operation nor during the course of postoperative radiotherapy.Conclusions A course of radiotherapy of DT54.2?Gy,on fractionation of DT1.8-2.0?Gy modal would not aggravate myasthenia.However,proper use of anti-cholinesterase,careful observation and timely drug-adjustment are necessary.