The findings suggest that ultrahypofractionation is a “great gain for patients and the health care system,” with lower costs, greater patient convenience, and potential improvements in treatment wait times, he added, and noted it might become a new standard of care for patients with low- or intermediate-risk prostate cancer in the future.
“There is rapidly accumulating evidence on the safety and efficacy of ultrahypofractionated radiotherapy for localized prostate cancer,” said Ronald C. Chen, MD, MPH, associate professor, department of radiation oncology at the University of North Carolina Chapel Hill and the UNC Lineberger Comprehensive Cancer Center.
Dr Chen is also the director of the UNC Cyberknife® Radiosurgery Program.
“This report, based on a randomized trial of 874 patients, specifically demonstrates that the treatment is safe,” Dr Chen told Cancer Therapy Advisor. “It showed that a 5-treatment ultrahypofractionated regimen doses not cause more short-term gastrointestinal or genitourinary toxicity compared to much longer treatments of 4-8 weeks.”
PACE-B joins the previously reported HYPO-RT-PC trial as a large randomized clinical study bolstering the case that localized prostate cancer can be treated “safely and effectively” with ultrafractionated radiotherapy, Dr Chen said.
“Many patients with localized prostate cancer likely have this option and can receive about 1 week of radiotherapy, much shorter than the 8 to 9 weeks of treatment patients used to receive only a few years ago,” he explained.
PACE-B’s toxicity outcomes reflect more precise delivery of radiation beams, Dr Chen noted. Radiotoxicities result from the incidental irradiation of nontarget, healthy tissues around the prostate. HYPO-RT-PC used an older technique, with 80% of patients undergoing 3dCRT, Dr Chen said. In contrast, PACE-B patients received SBRT, a much more advanced and precise form of external-beam radiotherapy.
The HYPO-RT-PC study demonstrated that ultrahypofractionated radiotherapy is “equally efficacious in controlling localized prostate cancer as conventionally fractionated radiotherapy,” Dr Chen said. “However, because this trial used older technology, the toxicity results of HYPO-RT-PC are not directly relevant to patients receiving treatment in the US today.”