Hypofractionated Radiotherapy Versus Conventional Radiotherapy In Patients With Intermediate-to High-risk Localized Prostate Cancer: A Meta Analysis

Prostate cancer(PCa)is a common male malignant tumor with increasing morbidity and mortality in China.The National Comprehensive Cancer Network(NCCN)and European Association of Urology(EAU)promote conventional radiotherapy with androgen deprivation therapy for intermediate-to high-risk localized PCa.However,conventional radiotherapy is implemented over a longer period of time(about 8 weeks),taking more medical resources.Due to its low ?/? value for PCa and based on the radiation biology model of PCa,PCa is more suitable for hypofractionated radiotherapy in theory.Most of the researches aim at hypofractionated radiotherapy in treatment of low-risk PCa,and the technique gets mature enough.But the studies of hypofractionated radiotherapy for intermediate-to high-risk PCa are less,and most of them are small sample size.The purpose of this work was to conduct a meta-analysis to compare the efficacy and adverse events profile of hypofractionated versus conventional radiotherapy for intermediate-to high-risk localized PCa,in hope of providing evidence for hypofractionated radiotherapy widely used in clincial.According to a specified search strategy,we retrieved the English database including PubMed,EMBASE and Web of Science and Chinese database including Chinese Journal Full-text Database,WanFang Database and Chinese Science and Technology Periodical Database.The types of search language are limited to English and Chinese,and the search time is not limited.The relevant databases were searched to collect the controlled clinical trials on hypofractionated radiotherapy and conventional radiotherapy in patients with intermediate-to high-risk localized PCa.Stata 12.0 was used for data analysis.Hazard ratio(HR)or risk ratio(RR)with its corresponding 95% confidence interval(CI)was used to describe the differences between two groups.According to the inclusion and exclusion criteria,a total of 5 controlled clinical trials involving 1621 patients with PCa were included in this meta-analysis.The results of the meta-analysis showed that overall survival(HR=1.00,95% CI: 0.85-1.17,P=0.980)and biochemical failure(RR=0.87,95% CI: 0.68-1.12,P=0.274)were similar in two groups.Compared with conventional radiotherapy,the incidence of acute adverse gastrointestinal event(grade ? 2)was higher in the hypofractionated radiotherapy(RR=1.94,95% CI: 1.23-3.06,P=0.004),but no significant difference was found in acute grade?3 gastrointestinal adverse reactions between two arms,the incidence of higher gastrointestinal adverse reactions was low.Acute genitourinary adverse event(grade?2)was similar among the groups(RR=1.03,95% CI: 0.92-1.14,P=0.626).Gastrointestinal(RR=1.17,95% CI: 0.90-1.51,P=0.238)or genitourinary(RR=1.11,95% CI: 0.94-1.30,P=0.228)late adverse events(grade?2)data were not significant differences between two radiotherapy schedules.Subgroup analysis showed that the incidence of acute gastrointestinal adverse events was significantly higher in hypofractionated radiotherapy group(RR=1.93,95% CI: 1.14-3.29,P=0.015<0.05)when the total dose of conventional radiotherapy group was ?78Gy.There was no significant difference in overall survival,biochemical failure,acute genitourinary adverse event and late adverse events(P > 0.05).Compared with conventional radiotherapy,hypofractionated radiotherapy has achieved similar clinical outcomes in patients with intermediate-to high-risk localized PCa.Although hypofractionated radiotherapy has an increased incidence rate of in acute gastrointestinal adverse events,the late gastrointestinal and genitourinary adverse events were similar in two groups,and the patients could be tolerable.