Shorter, Intensive Radiation Regimen Effective and Tolerable in Early-Stage Prostate Cancer

Cate Douglass

Researchers have discovered that shorter, more intensive radiation treatment for patients in the early stages of prostate cancer can be performed without compromising cancer control.

W. Robert Lee, MD, MEd, MS

Researchers have discovered that shorter, more intensive radiation treatment for patients in the early stages of prostate cancer can be performed without compromising cancer control.

Currently, the standard regimen lasts 8 weeks to treat the cancer; however, the study, conducted by a team of researchers at the Duke Cancer Institute, shortened that therapy to 5.5 weeks.

The study involved 1100 men who had been diagnosed with early-stage prostate and compared two treatment regimens to determine whether the cure rates were similar.

Half of the men were randomly assigned to receive either the 5.5-week schedule that provided 28 hypofractionated radiotherapy (H-RT) treatments and the other half was assigned to the standard 8-week regimen control arm, which consisted of a total of 41 conventional radiotherapy (C-RT) treatments.

Researchers found that the 5-year disease free survival (DFS) rate was about 85.3% for men in the 8-week trial and 86.3% in the 5.5-week program. Additionally, overall survival (OS) was also no different between the groups, 93.2% and 92.5%, respectively.

“This study has implications for public policy,” said lead study author W. Robert Lee, a professor in the Department of Radiation Oncology at Duke, in a statement. “Because the shorter regimen has advantages such as greater patient convenience and lower costs, it’s important to establishing whether we can cure as many patients with the shorter regimen. Our study provides that information for the first time.”

One potential drawback of the H-RT regimen, however, is slightly higher side effects in patients. The study’s authors reported mild gastrointestinal and genitourinary toxicity was observed more frequently in patients getting the higher daily dose, shorter frequency radiation. However, no differenceswere observed in more severe side effects, which were occurred <5% with either regimen. The study also noted that data on patient experience with side effects are still be analyzed.

"An estimated 220,000 men are expected to be newly diagnosed with prostate cancer each year in the United States, and the majority will have early-stage disease at low risk for recurrence,” Lee noted. “These findings should help guide clinical decisions, and doctors should be comfortable recommending a shorter radiotherapy course as an alternative to the conventional schedule.”

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Lee WR, Dignam JJ, Amin MB, et al. Randomized Phase III Noninferiority Study Comparing Two Radiotherapy Fractionation Schedules in Patients With Low-Risk Prostate Cancer [published online ahead of print April 4, 2016]. J Clin Oncol.