Patient-reported quality of life after stereotactic body radiotherapy (SBRT), intensity modulated radiotherapy (IMRT), and brachytherapy

Background and purpose Stereotactic body radiotherapy (SBRT) is being used for prostate cancer, but concerns persist about toxicity compared to other radiotherapy options. Materials and methods We conducted a multi-institutional pooled cohort analysis of patient-reported quality of life (QOL) [EPIC-26] before and after intensity-modulated radiotherapy (IMRT), brachytherapy, or SBRT for localized prostate cancer. Data were analyzed by mean domain score, minimal clinically detectable difference (MCD) in domain score, and multivariate analyses to determine factors associated with domain scores at 2-years. Results Data were analyzed from 803 patients at baseline and 645 at 2-years. Mean declines at 2-years across all patients were -1.9, -4.8, -4.9, and -13.3 points for urinary obstructive, urinary incontinence, bowel, and sexual symptom domains, respectively, corresponding to MCD in 29%, 20%, and 28% of patients. On multivariate analysis (vs. IMRT), brachytherapy had worse urinary irritation at 2-years (-6.8 points, p < 0.0001) but no differences in other domains (p > 0.15). QOL after SBRT was similar for urinary (p > 0.5) and sexual domains (p = 0.57), but was associated with better bowel score (+6.7 points, p < 0.0002). Conclusions QOL 2-years after brachytherapy, IMRT, or SBRT is very good and largely similar, with small differences in urinary and bowel QOL that are likely minimized by modern techniques.