ABSTRACT
Objective To evaluate the effect of setup errors upon the target area and the organs at risk (OAR) during radiotherapy for prostate cancer.Methods Twelve prostate cancer patients receiving treatment in the recent 1 year were randomly recruited in this study.The position of each patient was verified by using cone beam CT (CBCT) for 6-10 times during the treatment.In treatment planning system (TPS),the isocenter position was moved along the setup errors with averaging error value (Plan_A) and each CBCT value (Plan_F).The dose distribution was recalculated without changing the beam setting,weight factors and monitor units (MUs).The dose difference was statistically compared between the simulation and original plans (Plan_O).Results For clinical target volume (CTV) D95,there was a significant difference between Plan_A and Plan_O (P =0.008),whereas no significant difference was observed between Plan_F and Plan_O.There were significant differences between Plan_F and Plan_O,Plan_A and Plan_O (P=0.004,and 0.041) for the planned target volume (PTV) D95.For OAR,rectal V60,Dmax,left femoral V20,Dmax and right femoral Dmax significantly differed between Plan_F and Plan_O (P=0.026,0.015,0.041,0.049,0.003).However,only left femoral Dmax significantly differed between Plan_A and Plan_O (P=0.045).The movement in the superior-inferior (SI) direction was significantly correlated with the changes in the rectal V40,V50 and V60 and PTV D95 (r=-0.785,-0.887,-0.833,0.682).The movement in the anterior-posterior (AP) direction was significantly associated with the variations in the bladder V20,V30,V40,V50 and V60(r=-0.945,-0.823,-0.853,-0.818,-0.774).The evaluation indexes of all normal tissues in the re-plan could meet the clinical requirements.However,the volume of target prescription volume had different levels of deficit,and the deficit of Plan_F was greater than that of Plan_A.Conclusions The simulation results of averaging into the TPS underestimates the effect of daily setup errors on the dose distribution.The effect of setup errors on the dose distribution in target area is greater than that of normal tissues.Y-direction errors are more likely to cause the variations of the rectal and PTV dose,and the errors in the z-direction are inclined to cause the changes in the bladder dose.
ABSTRACT
Objective To systematically evaluate the clinical efficacy and safety between high-dose (74 to 80 Gy) and conventional-dose (64.0 to 70.2 Gy) conventionally fractionated external beam radiotherapy for stage T1b-4No-1M0 prostate cancer in this meta-analysis.Methods A literature search was performed in PubMea,ambasa,aochrane Librara,aeb of Scienca,aBa,aanfang Data,aNKI and Chongqing VIP to collect clinical trials on high-dose versus conventional-dose conventionally fractionated external beam radiotherapy of prostate cancer from the inception to July 1,2018.The included literatures were evaluated by Cochrane quality evaluation criteria and subject to meta-analysis by using Review Manager 5.3 statistical software.Results A total of 7 randomized controlled clinical trials involving 4 132 patients were included in the meta-analysis.The meta-analysis showed that the high-dose and conventional-dose groups yielded similar 10-year overall survival (RR=1.01,95％CI:0.96 to 1.07,P=0.64) and 10-year prostate cancer-specific survival (RR=1.01,95％CI:0.98 to 1.03,P=0.47).The biochemical failure rate in the high-dose group was significantly lower than that in the conventional-dose group (RR =0.78,95％CI:0.70 to 0.86,P＜0.01).Compared with the conventional-dose groua,ahe incidence of late grade ≥ 2 gastrointestinal and genitourinary adverse reactions (RR=1.48,95％CI:1.31 to 1.67,P＜0.01;RR=1.35,95％CI:1.06 to 1.73,P=0.02) was significantly higher in the high-dose group.Conclusion High-dose conventionally fractionated external beam radiotherapy has advantages in reducing the biochemical failure rate of patients with stage T1b-4N0-1M0 prostate cancer.Nevertheless,whether it can improve overall survival and prostate cancer-specific survival remains to be validated.High-dose radiotherapy also induce a higher incidence rate of late grade ≥ 2 gastrointestinal and genitourinary adverse reactions compared with conventional-dose radiotherapy.
ABSTRACT
Objective To systematically evaluate the efficacy and safety of brachytherapy (BT) combined with external beam radiation therapy (EBRT) and EBRT alone for prostate cancer.Methods Databases including PubMed,Web of Science,Cochrane Library,CNKI,WanFang Data and VIP were searched from the inception to July 2018 to collect the clinical trials which comparatively analyzed the efficacy and safety between EBRT plus BT and EBRT alone for prostate cancer.According to the inclusion and exclusion criteria,data of the included studies were extracted and the methodological quality was evaluated.Then,a meta-analysis was performed using RevMan 5.3.Results Ten studies of 23 393 patients were included,in which 6 were randomized controlled trials (RCTs) and the other 4 were non-RCTs.The 3-year biochemical progression-free survival (b-PFS)[OR=2.03(95％CI:1.11 to 3.73),P=0.02] and the 5-year b-PFS of intermediate-risk patients[OR=2.27(95％CI:1.49 to 3.45),P＜0.01] in the EBRT+BT group were significantly higher compared with those in the EBRT group.The 3-and 5-year b-PFS,5-year overall survival and 5-year metastasis-free survival did not differ between two groups.in the incidence of ≥ grade 2 acute[OR=1.44(95％CI:1.11 to 1.38),P＜0.01] and chronic genitourinary adverse reactions [OR=3.06(95％CI:1.37 to 6.80),P＜0.01],≥ grade 3 acute[OR=1.75 (95％CI:1.14 to 2.69),P=0.01] and chronic genitourinary adverse reactions[OR=3.41(95％CI:2.42 to 4.82),P＜0.01] in the EBRT group were significantly lower than those in the EBRT+BT group.The incidence of gastrointestinal adverse reactions did not significantly differ between two groups.Conclusion Compared with EBRT alone,EBRT combined with BT can effectively improve the 3-and 5-year b-PFS,whereas increase the incidence of genitourinary adverse reactions for patients with intermediate-risk prostate cancer.
ABSTRACT
Objective To evaluate the clinical efficacy and adverse events of intensity-modulated radiotherapy ( IMRT ) in the treatment of intermediate risk localized prostate cancer, and analyze the significance of prostate-specific antigen ( PSA) level changes. Methods Clinical data of 66 patients with intermediate risk localized prostate cancer admitted to our hospital between 2007 and 2018 were retrospectively analyzed. Sixty patients were treated with endocrine therapy before radiotherapy. The radiation field covered the pelvic lymph node drainage area in 6 cases. Forty-seven patients received image-guided radiotherapy ( IGRT) . The median dose in the prostate and seminal vesicle was 78 Gy and 48 Gy in the pelvic lymph node drainage area. The survival rate was calculated using the Kaplan-Meier method. Results The median age was 77 years. The median follow-up time was 71. 3 months. The 5-year sample size was 47. The 3-and 5-year overall survival (OS) was 98％ and 90％.The 3-and 5-year cancer-specific survival (CSS) was 100％ and 93％.The 3-and 5-year biochemical relapse-free survival was 97％ and 86％. The mean time of PSA declining to the nadir was 5. 83 months. The median level of PSA nadir was 0. 06 ng/ml after IMRT. The incidence of grade I andⅡearly adverse events in the urinary system was 38％ and 6％. The incidence of grade I andⅡearly adverse events in the gastrointestinal system was 21％ and 3％. The incidence of grade I andⅡadvanced-stage adverse events in the urinary system was 9％ and 2％. The incidence of grade I advanced-stage adverse events in the gastrointestinal system was 5％. Conclusions IMRT yields high clinical efficacy in the treatment of intermediate risk localized prostate cancer with a low risk of adverse events in the early and advanced stage. The monitoring of PSA after IMRT contributes to the assessment of clinical prognosis.
ABSTRACT
Objective To evaluate the prognosis and side-effects of three-dimensional conformal radiotherapy (3 DCRT) and intensity modulated radiotherapy (IMRT) for prostate carcinoma. Methods From 2001 to 2009, 62 patients with prostate carcinoma treated with radiotherapy were included in the retrospective analysis. Among them, 60 patients received IMRT while the other two received 3DCRT. There were 56 patients receiving androgen deprivation therapy before radiotherapy. The median dose was 78 Gy to 95% planning target volume (PTV) of the prostate and seminal vesicles, and the median dose to 95% PTV of the pelvic lymph nodes was 48 Gy. Results The median follow-up was 15.4 months. The 3-and 5-year overall survival (OS) rates were 92% and 83%, with the corresponding biochemical disease-free survival rates of 87% and 69%, and the distant metastasis-free survival (DMFS) rate of 77% and 55%, respectively. Patients with a PSA nadir ≤ 2 ng/ml had a 3-year OS of 94% and DMFS of 88%, compared with 56% and 11% (χ~2 = 16. 39, P < 0.01 for OS ; χ~2 = 28. 87, P < 0. 01 for DMFS) for those with a PSA nadir > 2 ng/ml. The incidence of grade 1 and 2 urinary toxicity was 32% and 0% for acute damage, 10% and 0% for late damage, respectively. The incidence of grade 1 and 2 intestinal toxicity was 19% and 3%. for acute damage, 5% and 3% for late damage, respectively. Conclusions Radiation therapy for patients with prostate carcinoma shows satisfactory outcomes with a good toleration. Monitor of PSA after radiotherapy has benefit for prognosis evaluation.