In a major development in the treatment of breast cancer, short-course, or hypofractionated, radiation therapy has demonstrated comparable outcomes to conventional postmastectomy radiation therapy while reducing treatment breaks and financial toxicity, according to data presented at the 2023 American Society for Radiation Oncology (ASTRO) Annual Meeting.1
Findings from the FABREC trial, the first study to report randomized phase III results of hypofractionation vs conventional fractionation in patients with mastectomy and implant-based reconstruction, showed no difference in oncologic outcomes, including distant recurrence, death, and local recurrence. Treatment with hypofractionation was also associated with improvement in specific quality-of-life domains, especially among younger patients.
Rinaa S. Punglia, MD, MPH
“Our results support the use of hypofractionated postmastectomy radiation for patients with implant-based reconstruction,” said senior study author Rinaa S. Punglia, MD, MPH, Associate Professor of Radiation Oncology at Harvard Medical School and radiation oncologist at Dana-Farber Cancer Institute, Boston.
As Dr. Punglia explained, implant-based reconstruction is commonly used for its psychological benefits and shorter recovery compared with autologous reconstruction, but radiation therapy further complicates the process. Hypofractionation—shorter radiation schedules with higher daily doses—has been increasingly adopted recently because of the equivalent long-term oncologic and superior quality-of-life outcomes, leading to the FABREC study.
The phase III FABREC trial evaluated hypofractionation vs conventional fractionation radiation in patients who had undergone mastectomy and immediate implant-based reconstruction. Conducted across 16 institutions nationally from 2018 to 2021, the study randomly assigned patients to conventional fractionation consisting of 25 fractions over 5 weeks (50 Gy total; n = 201) or hypofractionated radiation consisting of 16 fractions over roughly 3 weeks (42.56 Gy total; n = 199). The primary study endpoint was improvement in the Physical Well-Being domain of FACT-B at 6 months, controlling for age.
Benefits of Accelerated Treatment
As Dr. Punglia reported, analysis revealed no differences in oncologic outcomes, including recurrence, death, and local recurrence, between treatment arms. The primary study outcome of physical well-being was also comparable between the two arms. However, the younger patients who received hypofractionation had higher physical well-being scores than those that received conventional fractionation, at 6 months.
“Interestingly, younger patients randomly assigned to hypo-fractionation had higher physical well-being scores than those randomly assigned to conventional fractionation,” Dr. Punglia explained. “[Young patients] also reported fewer hours of unpaid time off from work and improved overall quality of life.”
KEY POINTS
- The phase III FABREC study, which evaluated the use of hypofractionated vs conventional postmastectomy radiation therapy in patients with implant-based reconstruction, showed comparable oncologic outcomes for short-course radiation, with fewer treatment breaks and less financial toxicity.
- Randomization to hypofractionation was also associated with improvement in specific quality-of-life domains, especially among younger patients, compared with conventional fractionation.
Study results showed that 7.7% of the patients in the conventionally fractionated arm had a treatment break (average = 3.3 days), as compared with 2.7% of patients in the hypofractionated arm (average = 2.8 days; P = .03). Although chest wall toxicity was experienced by 39 patients, said Dr. Punglia, there was no difference in chest wall toxicity or any other toxicity outcomes by treatment arm.
Treatment with short-course radiation was also associated with a reduction in financial toxicity, study authors reported. Among patients who took time off from work for treatment (n = 51), the mean hours of unpaid time were 125.8 hours for conventional fractionation vs just 73.7 hours for hypofractionated radiation (P = .046).
“Overall, the FABREC study supports the use of hypofractionated postmastectomy radiation for patients undergoing implant-based reconstruction,” Dr. Punglia concluded. “This could lead to a shift toward hypofractionation in these patients, improving their overall well-being.”
Future research may aim to study the long-term effects of hypofractionation and its impact on a wider patient population, authors of the study noted.
DISCLOSURE: This study was funded through a Patient-Centered Outcomes Research Institute (PCORI) Award (CER-1609-36063). Dr. Punglia reported no conflicts of interest.
REFERENCE
1. Wong JS, Tramontano A, Pellegrini C, et al: Patient-reported and toxicity results from the FABREC study. 2023 ASTRO Annual Meeting. Abstract LBA05. Presented October 2, 2023.
