Hypofractionated RT: A Potential New Standard Treatment for Certain Breast Cancers

In Clinical Studies News by Barbara Jacoby

By: Leah Lawrence

From: cancertherapyadvisor.com

A new study suggested that moderately hypofractionated whole-breast irradiation was safe and effective, and could be recommended as a standard therapy for breast-only radiotherapy in women who undergo breast-conserving surgery for node-negative early breast cancer.

The study randomly assigned 1854 women to receive radiotherapy at either 50 Gy in 25 fractions or the hypofractionated rate of 40 Gy in 15 fractions.

There was no significant difference in the 3-year rates of induration between women who received 50 Gy compared with those who received the hypofractionated dose (11.8% vs 9.0%; P =.07).

Patients assigned to either arm had low rates of telangiectasia, dyspigmentation, scar appearance, edema, and pain. The rate of cosmetic outcome and patient satisfaction were high for both groups. Either no difference was found between the arm or outcomes favored the hypofractionated rate.

The 9-year overall survival rate was 93.4% for women in both arms of the study, and differences in the 9-year risk of locoregional recurrence was small for 50 Gy vs 40 Gy (3.3% vs 3%).

“Our trial included a high number of patients from few departments, and there was no hesitation including patients with large breast volume, smokers, patients receiving chemotherapy, or patients with a relatively high recurrence risk (estrogen receptor [ER]2/human epidermal growth factor receptor [HER2]2 or HER2+) because the intention was to explore the potential limits of hypofractionation,” the researchers noted. “This is in harmony with other randomized trials and therefore indicates that 50 Gy is excessive treatment for most patients treated with breast-only radiotherapy.”

However, the researchers did note that the hypofractionated radiotherapy may be insufficient for women with locally advanced disease or other high-risk features.

Disclosure: The authors reported financial relationships with the pharmaceutical industry. For a full list of disclosures, please refer to the original study.

Reference

Offersen BV, Alsner J, Nielsen HM, et al. Hypofractionated versus standard fractionated radiotherapy in patients with early breast cancer or ductal carcinoma in situ in a randomized phase III trial: The DBCG HYPO trial. J Clin Oncol. Published online September 10, 2020. doi:10.1200/JCO.20.01363