Ultra-Hypofractionated Radiation May Mitigate Breast Cancer Recurrence

CancerNetwork® spoke with Bin Gui, MD, a fourth-year radiation oncology resident at the Northwell Health Cancer Institute, about the efficacy of ultra-hypofractionated radiation (UHFRT) among older patients with early-stage breast cancer presented at the 2024 American Society of Radiation Oncology (ASTRO) Annual Meeting.¹

Gui briefly explained the methodology employed when conducting the study assessing UHFRT in this population. Patients were treated using regimens employed in the phase 3 FAST-Forward trial (ISRCTN19906132) and an accelerated partial breast irradiation (APBI) trial (NCT02104895).^2,3

He further stated that there was compliance among all patients assigned to radiotherapy vs those assigned to radiation plus endocrine therapy, in which only 24% complied partly due to adverse effects. He described how low-grade or late toxicities occurred infrequently in patients undergoing radiation with or without endocrine therapy.

Results from the trial presented at ASTRO found that at a 10-month follow-up, no ipsilateral breast tumor recurrence (IBTR) occurred in the UHFRT cohort. Furthermore, there was an absence of grade 3 or 4 toxicities, and minimal low-grade (UHFRT alone, 2%; UHFRT plus ET; 0%) and late (2% vs 0%) toxicities were observed with radiation therapy.

Transcript:

Over 1000 [patients] with early-stage breast cancer were treated in our center back within the [past] 4 years. Seventy-one [patients] met the low-risk inclusion criteria and were treated with either whole breast FAST-Forward regimens or accelerated partial breast irradiation [APBI] regimens. What did we find here? The median tumor size was 0.8 cm. [Although] the compliance with radiation was 100%, the compliance with the endocrine therapy was only 24% either due to refusal or termination of endocrine therapy due to [adverse] effects. We have a median follow-up of 10 months, and there was no local recurrence in the entire cohort, and there was no grade 3 or 4 toxicity. The grade 2 acute toxicity, late toxicity, and cosmetic outcomes were [all] low for radiation plus endocrine therapy, or radiation alone.

References

1. Gui B, Ojo O, Ottensoser L, et al. Ultra-Hypofractionated Radiation in Older Patients with Low Risk Early-Stage Breast Cancer. Presented at the 2024 American Society for Radiation Oncology (ASTRO) Annual Meeting; September 29 – October 2, 2024; Washington, DC. Poster 2683
2. Brunt AM, Haviland JS, Wheatley DA, et al. One versus three weeks hypofractionated whole breast radiotherapy for early breast cancer treatment: the FAST-Forward phase III RCT. Health Technol Assess 2023;27(25). doi:10.3310/WWBF1044
3. Meattini I, Marrazzo L, Saieva C, et al. Accelerated partial-breast irradiation compared with whole-breast irradiation for early breast cancer: long-term results of the randomized phase III APBI-IMRT-Florence trial. J Clin Oncol. 2020;38(35):4175-4183. doi:10.1200/JCO.20.00650.