Radiation is an integral part of treatment in breast cancer. While multiple modalities, such as 3D conformal radiotherapy, IMRT, and proton therapy, are utilized to deliver this radiation, several different treatment regimens have been evaluated and validated with convincing evidence. In the times of COVID-19, we have seen a trend in treatment schedules that fall in line with strategies used to suppress the wave of COVID-19 infections, such as reducing treatment courses to as few as five treatments in some countries. These measures are temporary and are not addressed here.
The standard of care in early breast cancer, proven through strong evidence-based research, has been a 6-7 week course of radiation typically delivered after surgery or after chemotherapy in women receiving chemo. A shorter (hypo-fractionated), 4-week course of treatment has been studied and used in Canada, UK, and several European countries with similar outcomes. Although delivered over a shorter period of time, the dose of radiation per day is slightly greater than that delivered each day in the standard 7-week course.
The NCCN (National Comprehensive Cancer Network) guidelines incorporated the hypofractionated (shorter course) course of radiation in early breast cancer patients who have undergone breast-conserving surgery, i.e., lumpectomy. This hypo-fractionated course of radiation is a four-week course of treatment as opposed to the conventional 7-week course.
In August of 2020, the International Journal of Radiation Oncology Biology Physics published a multicenter study from Canada evaluating the acute toxicity and quality of life (QOL) in patients treated with this abbreviated radiation course¹. Enrolled in the study were women who had undergone breast-conserving surgery (lumpectomy) with negative (clear) surgical margins and had no involvement of lymphnodes with cancer. Acute skin toxicity was evaluated at baseline and then every two weeks for up to 8 weeks. Initially, this was similar in both groups. However, at the eight-week mark, the patients treated with the hypo-fractionated course did better. The QOL assessment included eight domains:
- Skin side effects
- Breast side effects
- Surgical side effects
At the 6-week post-treatment follow-up, patients who had undergone the shorter course of treatment had an overall better QOL in most domains but especially in skin side effects, breast side effects, and attractiveness.
This study shows that a select group of patients would benefit from a shorter course of treatment. It is essential to evaluate each individual patient, their medical history, specific cancer characteristics, surgical and pathological features to select patients for this treatment course, as we believe that each patient is unique and that one size certainly does not fit all.
- Acute toxicity and Quality of Life of Hypofractionated Radiaton Therapy for Breast Cancer – Julie Arsenault et al IJROBP Vol 107, No 5. Pp 943-948, Aug 2020