Conventional vs. Hypofractionation Radiation for High-Risk Prostate Cancer Patients (CHIRP): 24 Months Patient-Reported Quality of Life Outcomes of the Randomized Phase II CHIRP Trial.

Purpose/Objective(s) The CHIRP study is a randomized phase II clinical trial that compared clinical outcomes between standard fractionation (78Gy in 39 fractions) and hypofractionation (68Gy in 25 fractions) in the treatment of high-risk prostate cancer. We performed a quality of life (QoL) sub-study to assess patient-reported outcomes up to 24 months post therapy. Materials/Methods Men with high-risk prostate cancer (stage T3/T4 and/or PSA ≥20 ng/ml and/or Gleason score 8 to 10) without clinical or radiological evidence of nodal or distant metastases were included in the CHIRP trial. QoL data was collected through the Expanded Prostate Cancer Index Composite (EPIC) and the Short Form 12 (SF12) health-related QoL questionnaire at baseline, 3 months, 6 months, 12 months, 18 months and 24 months post treatment. We assessed change from baseline (follow-up score minus bassline score) to account for differences in baseline comorbidities. Analysis of Variance (ANOVA), using a significance level of 0.05, was used to identify differences between the two groups. Results A total of 96 participants were included in the QoL sub-study, with 49 patients in the hypofractionation arm and 47 patients in the standard fractionation arm. Baseline urinary function favored patients in the standard arm (P = 0.04). All other baseline QoL parameters were balanced. At 3 months (P = 0.155), 6 months (P = 0.197), 12 months (P = 0.016) and 18 months (P = 0.120) post treatment, the bowel bother scores trended to favor the standard fractionation arm, and was statistically significant at 12 months (P = 0.016). At 6 months (P = 0.187), 12 months (P = 0.063) and 18 months (P = 0.017) post treatment, the SF12 physical component score (PCS) trended to favor the hypofractionation arm, and was statistically significant at 18 months (P = 0.017). At 24 months, there were no differences in QoL scores between the 2 groups. Conclusion The patient-reported QoL scores were similar between the standard fractionation arm (78Gy in 39 fractions) and the hypofractionation arm (68Gy in 25 fractions) up to 24 months after radiotherapy. Early statistically significant differences in bowel bother and physical component score were no longer present at 24 months.