Clinical efficacy and toxicity of intensity-modulated radiation therapy following prostatectomy for 98 elderly patients with prostate cancer

Abstract

Objective To evaluate the clinical efficacy and toxicity of intensity-modulated radiation therapy (IMRT) following prostatectomy for elderly patients with prostate cancer. Methods Ninety-eight prostate cancer patients receiving IMRT after prostatectomy were included in this study. The median age was 68 years old. The number of patients with low-, middle-and high-risk prostate cancer was 10, 21 and 67, respectively. Two patients had oligometastases (pelvic bone metastases). Sixty-four patients were treated with IMRT combined with endocrine therapy. Among them, 43 cases received adjuvant volumetric modulated arc therapy (VMAT), and 55 patients received salvage IMRT.The median radiotherapy dose was 72 Gy for the tumor bed. Twenty-nine patients received radiotherapy of the pelvic node region with a median dose of 50 Gy. Results The median follow-up time was 40 months. The 5-year overall survival (OS), biochemical recurrence-free survival (BRFS) and local control (LC) were 90%, 76% and 100%, respectively. The OS (88.8% vs. 90.8%, P=0.94), BRFS (75.9% vs. 71%, P=0.79) or LC (100% vs. 100%, P=0.32) did not significantly differ between the adjuvant and salvage radiotherapy groups, respectively. The incidence of grade I-Ⅱ late rectal toxicities was 24.1%, and no ≥ grade 3 late toxicity was observed. The incidence of grade 1-2 late bladder toxicities was 29.9%, and 3.4% for grade 3. Conclusion IMRT following prostatectomy yields high clinical efficacy and slight late toxicities in elderly patients with prostate cancer. Key words: Prostate neoplasms/intensity-modulated radiotherapy; Prostate neoplasms/ volumetric modulated arc therapy; Treatment outcome