ASTRO updates prostate cancer radiation guidelines, expands role of shortened treatments
The American Society for Radiation Oncology (ASTRO) has updated its clinical practice guidelines for radiation therapy in localized prostate cancer.
The new guidelines recommend shorter-course treatment over conventional radiation schedules and expanding the role of stereotactic body radiation therapy (SBRT) for appropriate patients. Published in Practical Radiation Oncology, the update replaces ASTRO’s 2018 recommendations to reflect the growing body of evidence showing that hypofractionated external beam radiation therapy (EBRT) can maintain cancer control while reducing treatment time.
“SBRT has moved from a promising alternative to a standard treatment option for many patients with localized prostate cancer,” guideline task force chair Scott C. Morgan, MD, a radiation oncologist at The Ottawa Hospital and professor of radiation oncology at the University of Ottawa, said in a release. “These recommendations give clinicians clear direction on using shorter-course treatment safely while preserving the excellent outcomes patients expect from definitive radiation therapy.”
Hypofractionation delivers higher doses of radiation per session, allowing patients to complete treatment in fewer visits. Moderate hypofractionation typically takes four to six weeks, while ultrahypofractionation, most commonly delivered as SBRT, can be completed in five sessions over one to two weeks.
The updated guideline recommends moderate hypofractionation over conventional fractionation for patients across all prostate cancer risk groups who choose EBRT. Randomized trials involving more than 7,000 patients have demonstrated comparable cancer control, side effects and quality of life with shorter treatment schedules.
The recommendations also establish ultrahypofractionation as a standard option for many patients, including those with low-risk disease who decline active surveillance and those with intermediate-risk disease receiving radiation to the prostate and seminal vesicles. For patients with high-risk or very high-risk disease, ultrahypofractionation is conditionally recommended.
The guideline emphasizes that treatment decisions should account for individual disease characteristics, baseline urinary function and patient preferences. For patients with significant pre-existing urinary symptoms, moderate hypofractionation is conditionally preferred over ultrahypofractionation because the shorter regimen may increase treatment-related urinary side effects.
Recommended moderate hypofractionation schedules include 60 to 62 Gy in 20 fractions or 70 Gy in 28 fractions. For ultrahypofractionation, the guideline conditionally recommends 36.25 to 40 Gy in five fractions; regimens using fewer than five fractions are not recommended outside clinical trials.
Equitable access also is emphasized in the new guideline. Shorter treatment schedules can reduce travel, time away from work and other burdens associated with radiation therapy, but national data show that use of hypofractionated treatment has varied by age, race, socioeconomic factors and treatment setting.
These are just a few of the highlights from the new guideline. For the full detailed update, click here.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She began covering the medical imaging industry for Innovate Healthcare in 2021.