Hypofractionated radiation treatment following mastectomy in early breast cancer: the Christchurch experience.

INTRODUCTION: Although hypofractionated radiotherapy (HFRT) has become an accepted option for whole-breast irradiation after breast-conserving surgery, there is limited evidence to support HFRT to the chest wall following mastectomy. We retrospectively analysed post-mastectomy patients treated with HFRT in Christchurch to determine whether HFRT yields acceptable efficacy and toxicity.

METHODS: The Christchurch oncology database was used to identify breast cancer patients treated with adjuvant HFRT to the chest wall following a mastectomy between 2003 and 2008. Eligible post-mastectomy patients were treated with 40 Gy in 16 daily fractions. Treatment outcomes assessed included local recurrence-free survival, breast cancer survival, overall survival and acute toxicities.

RESULTS: One hundred thirty-three patients were identified. The median follow-up period was 5.03 years. Three patients had a local recurrence as a first event, resulting in 5-year local recurrence-free survival of 97.6%. Five-year overall survival and 5-year breast cancer survival were 74.7% and 77.7%, respectively. The prospectively assessed acute toxicities were mostly grade 1. In particular, the incidence of grade 2 skin toxicity was 10.7%, and no patients experienced grade 3 skin toxicity.

CONCLUSION: The high local control rate with HFRT, combined with acceptable toxicity and the practical benefits of a shorter treatment time, supports its ongoing use in the eligible patient group. A randomised controlled trial would be necessary to more completely assess the acute and long-term toxicity of HFRT compared with standard fractionation.