Published in the Green Journal, the Mayo Clinic group reported outcomes of 51 women among who 42 had bilateral reconstruction treated with unilateral IMPT. Conventional fractionation (median 50 Gy/25 fractions) was administered in 37 (73%) and hypofractionation (median 40.5 Gy/15 fractions) in 14 (27%) patients. Median mean heart, ipsilateral lung V20Gy, and CTV-IMN V95% were 0.6 Gy, 13.9%, and 97.4%. Maximal acute dermatitis grade was 1 in 32 (63%), 2 in 17 (33%), and 3 in 2 (4%) patients.

Among irradiated breasts, hypofractionation was significantly associated with reconstruction failure. This study concluded that IMPT following immediate breast reconstruction spared underlying organs and had low rates of acute toxicity. Reconstruction complications are more common in irradiated breasts, and reconstructive outcomes appear comparable with photon literature.