Clinical efficacy of intensity-modulated radiotherapy in treatment of 66 patients with intermediate risk localized 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 and Ⅱ early adverse events in the urinary system was 38% and 6%. The incidence of grade I and Ⅱ early adverse events in the gastrointestinal system was 21% and 3%. The incidence of grade I and Ⅱ advanced-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. Key words: Prostate neoplasm/radiotherapy; Treatment outcome; Prostate-specific antigen