Stereotactic body radiotherapy with flattening filter-free beams for prostate cancer: assessment of patient-reported quality of life.

Stereotactic body radiotherapy (SBRT) is an emerging treatment approach reported as safe and effective strategy for low- and intermediate-risk prostate cancer patients. End point of the current study is to appraise the patient-reported quality of life according to the expanded prostate cancer index composite (EPIC) questionnaire. In the framework of a prospective mono-institutional phase II trial, EPIC questionnaire was dispensed (up to 1 year after treatment) to a cohort of 46 patients of 72 treated with 5 fractions of 7 Gy each to the prostate. SBRT was delivered with RapidArc VMAT with 10 MV flattening filter-free photon beams. Median follow-up of patients was 14.5 months (range: 6-23). Acute rectal toxicity was mild (only 23/72 cases with G1-2 and no G3-4) as well as urinary (50/72 G1-2 and no G3-4). At the moment, four cases of G1 late rectal toxicity and 22 cases of G1 urinary (1 of G2) were reported. Urinary, rectal, sexual, and hormonal scores resulted stable over time: 1 year scores resulted, respectively, in -0.3, +2.8, -1.7, and -2.8 % variations with respect to baseline. No significant differences were observed also when data were stratified according to functional and bother sub-scales. Stereotactic body radiotherapy (SBRT) treatment of prostate with RapidArc and high-intensity photon beams resulted to be well tolerated by patients with mild toxicity profiles and good patient-reported quality of life perception for the first year after treatment. Longer follow-up in the trial cohort is in progress.