A higher-dose, shorter form of radiation is safe, effective, and no more damaging to the breast tissue or skin of women with breast cancer under age 50 than it is in older patients, according to findings led by researchers from Perlmutter Cancer Center at NYU Langone Health, and presented at the annual meeting of the American Society for Radiation Oncology (ASTRO) in San Diego.
The study results address two radiation therapy techniques, including the more conventional approach (radiation daily for 6 or 7 weeks) or hypofractionated whole breast radiotherapy, a newer approach where patients receive higher doses over a shorter 3- to 4-week period.
Hypofractionated Whole Breast Radiotherapy
hyperfractionated whole breast radiotherapy is preferred by many because it cuts the treatment time in half, and therefore reduces the burden on patients in terms of trips to the clinic and cost, said the study authors. Seminal studies more than a decade ago found the shorter technique to be as effective and safe as the longer schedule. However, few younger patients were included in these studies, calling into question whether the results could be applied to the younger group.
Also of concern to some physicians were “late side effects,” said the researchers, such as hardening of the breast tissue, breast shrinkage, and skin changes.
Given a lack of evidence needed to dispel these concerns, 2011 ASTRO guidelines on hypofractionated whole-breast radiation recommended the shorter treatment course for qualified patients aged 50 or older, but not for younger patients.
New Rigorous Scientific Evidence
“Our new study provides rigorous scientific evidence that hypofractionated radiation therapy is safe and effective in women under 50,” said lead study author Naamit Gerber, MD, Assistant Professor of Radiation Oncology at NYU School of Medicine. “Based on this new evidence, it is important that the guidelines for hypofractionated radiation after lumpectomy change to include younger women.”
Naamit Gerber, MD
Silvia Formenti, MD
An estimated 292,130 new cases of breast cancer were diagnosed in 2015, 60,310 (21%) of which were in women under age 50. Of women with stage I or II breast cancer, 49% receive lumpectomy followed by radiation, the majority of whom are candidates for whole breast hypofractionated irradiation.
“We estimate that the potential exists for tens of thousands of patients to receive this less burdensome form of radiation each year,” said Dr. Gerber.
Thanks to a research effort led by Silvia Formenti, MD, who at the time co-led the Breast Cancer Research Program at NYU Langone, and is currently on faculty at Weill Cornell Medical College, four prospective studies looking at different hypofractionation regiments did not rule out enrolling younger patients. As such the researchers were equipped to determine whether younger women with breast cancer could benefit from hypofractionated whole breast radiotherapy and a shorter schedule. ■
1. Shaikh F, Chew J, Perez, CA, et al: Hypofractionated whole breast irradiation in women less than 50 years old treated on prospective protocols: A report on long-term cosmesis. 2017 ASTRO Annual Meeting. Abstract 13. Presented September 26, 2017.