Formal discussant of the PCS5 trial, Sophia C. Kamran, MD, Director of Diversity, Equity, and Inclusion, Department of Radiation Oncology at Massachusetts General Hospital and Assistant Professor of Radiation Oncology at Harvard Medical School, said the goal of trials like this one is to optimize outcomes. “What is known about hypofractionated radiotherapy is not new, but prior studies have either included a small percentage of patients with high-risk prostate cancer, and the radiation field also included the prostate and seminal vesicles alone. This study specifically included pelvic nodal radiation, which has previously been debatable,” Dr. Kamran noted. In the PCS5 trial of high-risk patients with prostate cancer, there was no significant difference between hypofractionated radiotherapy (delivered as standard pelvic radiation plus concomitant hypofractionated boost) and conventional radiotherapy in these patients who received pelvic nodal irradiation.

Sophia C. Kamran, MD

“There was more acute gastrointestinal toxicity in the hypofractionated arm, but this difference disappeared by 1 year. There was more late genitourinary toxicity in the standard arm. No significant difference between the arms was observed for all clinical outcomes at 3, 5, and 7 years,” Dr. Kamran stated. “My conclusion is hypofractionated radiotherapy is equivalent to standard radiotherapy for high-risk prostate cancer when including the pelvis, and it is an appropriate option. Many of us already incorporate this into our practice,” she added.

Open questions are whether treatment can be shortened even more than 5 weeks and whether hypofractionated radiotherapy to the pelvic nodes can improve outcomes without increasing toxicity. “This is currently being studied,” she said. 

DISCLOSURE: Dr. Kamran’s spouse is employed by Sanofi Genzyme.