Hypofractionated volumetric-modulated arc therapy for localized intermediate-high risk prostate cancer: a clinical analysis

Abstract

Objective To evaluate the efficacy and adverse reaction of hypofractionated volumetric-modulated arc therapy (VMAT) for localized intermediate-high risk prostate cancer. Methods 23 patients with localized intermediate-high risk prostate cancer were enrolled in this study between Dec. 2013 and Mar. 2016. All patients received hypofractionated VMAT (2.5 Gy/fx, 28 fractions, total 70 Gy) to the prostate and seminal vesicles. Only 6 high risk patients also received prophylactic irradiation to the pelvic lymph nodes concurrently (2 Gy/fx, 25 fractions). All the patients received androgen deprivation therapy. Results After a median follow-up of 13 months, prostate specific antigen (PSA) was reduced from 12.90 ng/ml(5.00~187.00 ng/ml) before radiotherapy to 0.13 ng/ml(0.10~5.20 ng/ml) after radiotherapy. 1-year biological recurrence-free survival rate was 77.5 %, and 1-year locoregional recurrence-free survival rate was 87.7 %. 8 patients (34.8 %) experienced grade 1 acute genitourinary toxicity, while 5 patients (21.7 %) experienced grade 2, with no late genitourinary toxicity. 12 patients (52.2 %) experienced grade 1 acute gastrointestinal toxicity, 8 patients (34.8 %) grade 2, and 2 patients (8.7 %) experienced grade 2 late gastrointestinal toxicity. Conclusion The efficacy after 2.5 Gy/fx, 28 fractions' hypofractionated VMAT for localized intermediate-high risk prostate cancer is favorable, with low toxicity. Key words: Prostate neoplasms; Radiotherapy; Treatment outcome; Toxic actions