ASTRO 2021: Conventional vs Hypofractionated Radiation for High Risk Prostate Cancer Patients (CHIRP): 24 months Patient Reported Quality of Life Outcomes of the Randomized Phase II CHIRP Trial

( The 2021 American Society for Radiation Oncology (ASTRO) Hybrid Annual Meeting included a presentation by Dr. Fan Yang providing 24-month patient-reported quality of life outcomes from the randomized phase II trial of conventional versus hypofractionated radiation for high risk prostate cancer patients (CHIRP).

Given the low alpha/beta ratio of prostate cancer, hypofractionation may provide a therapeutic advantage over conventional radiotherapy. At the University of Alberta, Dr. Yang and colleagues recently completed the phase II CHIRP trial noting no differences in clinician reported toxicities between conventional and hypofractionated radiotherapy.1 However, patient reported outcomes can differ significantly from physicians’ rating of treatment side-effects.

In CHIRP, 111 patients with high-risk prostate cancer were randomly assigned to prostate plus pelvic nodal radiation therapy with either hypofractionated radiotherapy (68 Gy in 25 fractions) or conventionally fractionated radiotherapy (78 Gy in 39 fractions) and 18 months of androgen suppression therapy. The workflow for the CHIRP trial is as follows:


Quality of life data collection included the expanded prostate cancer index composite (EPIC) and the short form (SF12) health-related quality of life questionnaire. The baseline characteristics for the patients included in this trial are as follows:


Generally, there was little difference between the hypofractionated versus conventionally fractionated patients with regards to patient reported urinary outcomes at baseline, 3 months, 6 months, 12 months, 18 months, and 24 months:


Similarly, there was little difference in sexual function, and overall patient satisfaction (in both arms, over 90% of patients were either satisfied or very satisfied with treatment 24 months post radiotherapy) between the groups over the course of the follow-up:


With regards to bowel bother scores (changes from baseline), there were some differences at 12 months favoring conventionally fractionated radiotherapy, however with longer follow-up (24 months), there was no difference in patient reported outcomes:


Dr. Yang concluded his presentation of 24-month patient reported outcomes of the CHIRP trial with the following take-home messages:

  • There were no major differences in patient-reported quality of life outcomes between conventional and hypofractionated radiotherapy
  • Early differences in bowel both and SF-12 physical component scores were no longer present at 24 months post radiotherapy
  • These patient-reported results are congruent with the clinician-reported toxicity data from the CHIRP trial [1], and further support the use of hypofractionation in high-risk prostate cancer

Presented by: Fan Yang, PhD, Division of Radiation Oncology, University of Alberta, Edmonton, Canada

Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the 2021 American Society for Radiation Oncology (ASTRO) Hybrid Annual Meeting, Sat, Oct 23 – Wed, Oct 27, 2021.


  1. Wang MH, Vos LJ, Patel S, et al. Clinical Outcomes of the CHIRP Trial: A Phase II Prospective Randomized Trial of Conventionally Fractionated Versus Moderately Hypofractionated Prostate and Pelvic Nodal Radiation Therapy in Patients with High-Risk Prostate Cancer. Practical Radiation Oncology. 2021;11(5):384-393.


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