Top Line: What are the outcomes of reirradiation for locoregionally recurrent breast cancer?
The Study: Here is a look back at Mayo’s experience for reirradiation of the breast or chest wall over the past two decades. Across 72 patients, median prior dose was 60 Gy and median reirradiation dose was 45 Gy. There was a rough 60 / 40 split on curative / palliative intent, and half of patients had gross disease at time of radiation. Roughly three-quarters received treatment with photons and one-quarter protons. At a median follow-up of nearly 2 years, grade 3 toxicity was experienced by 13% (10% acute dermatitis + 3% late skin necrosis). The most important determinant of toxicity was something we can’t control: time interval between radiation. Among the 37 patients without gross disease treated with curative-intent, 93% were free from another locoregional failure and 77% still alive at 2 years. Two-thirds experienced low-grade fibrosis and 9 (14%) developed telangiectasias. Rib fracture occurred in 14 patients (19%) at a median of 11 months, 10 of which were incidentally discovered on imaging. Of note, the only two cases of brachial plexopathies occurred in the absence of axillary reirradiation but in the presence of a malignant axillary tumor.
TBL: Reirradiation for resected recurrent breast cancer is tolerable and can achieve excellent local control. | Fattahi, Adv Radiat Oncol 2022