Is hypofractionated whole pelvis radiotherapy (WPRT) as well tolerated as conventionally fractionated WPRT in prostate cancer patients? The HOPE trial.

Patients with high-risk prostate cancer are at increased risk of lymph node metastasis and are thought to benefit from whole pelvis radiotherapy (WPRT). There has been recent interest in the use of hypofractionated radiotherapy in treating prostate cancer. However, toxicity and cancer outcomes associated with hypofractionated WPRT are unclear at this time. This phase II study aims to investigate the impact in quality of life associated with hypofractionated WPRT compared to conventionally fractionated WPRT.

Fifty-eight patients with unfavourable intermediate-, high- or very high-risk prostate cancer will be randomized in a 1:1 ratio between high-dose-rate brachytherapy (HDR-BT) + conventionally fractionated (45 Gy in 25 fractions) WPRT vs. HDR-BT + hypofractionated (25 Gy in 5 fractions) WPRT. Randomization will be performed with a permuted block design without stratification. The primary endpoint is late bowel toxicity and the secondary endpoints include acute and late urinary and sexual toxicity, acute bowel toxicity, biochemical failure-, androgen deprivation therapy-, metastasis- and prostate cancer-free survival of the hypofractionated arm compared to the conventionally fractionated arm.

To our knowledge, this is the first study to compare hypofractionated WPRT to conventionally fractionated WPRT with HDR-BT boost. Hypofractionated WPRT is a more attractive and convenient treatment approach, and may become the new standard of care if demonstrated to be well-tolerated and effective.

This trial was prospectively registered in ClinicalTrials.gov as NCT04197141 on December 12, 2019.

BMC cancer. 2020 Oct 09*** epublish ***

Lucas C Mendez, Andrew J Arifin, Glenn S Bauman, Vikram M Velker, Belal Ahmad, Michael Lock, Varagur M Venkatesan, Tracy L Sexton, George B Rodrigues, Jeff Chen, Bryan Schaly, Andrew Warner, David P D'Souza

Division of Radiation Oncology, London Regional Cancer Program, 800 Commissioners Road East, London, Ontario, N6A 5W9, Canada. ., Division of Radiation Oncology, London Regional Cancer Program, 800 Commissioners Road East, London, Ontario, N6A 5W9, Canada., Department of Physics and Engineering, London Regional Cancer Program, 800 Commissioners Road East, London, Ontario, N6A 5W9, Canada.