Effect of reduction mammoplasty on acute radiation side effects and use of lumpectomy cavity boosts.

[PURPOSE] Reduction mammoplasty (RM) during breast-conserving surgery is popular among women with large-volume breasts because it reduces redundant breast folds and may decrease skin-related morbidity from radiation therapy. However, RM may obscure the lumpectomy cavity (LC) and pose challenges to administering an LC boost, potentially affecting local control. We investigated the impact of RM on acute side effects and use of LC boosts.

[METHODS AND MATERIALS] The records of 645 consecutive women treated with whole-breast irradiation at an urban university and 2 community practices between January 2012 and December 2014 were reviewed on an institutional review board-approved study. The primary endpoint was grade ≥3 radiation dermatitis; the secondary endpoint was use of LC boost. Student 2-sample t tests, Pearson χ tests, Fisher exact tests, and univariate and multivariable logistic regression analyses were performed.

[RESULTS] Forty-three (7%) RMs were performed in 650 treated breasts. No significant differences in grade 3 toxicities were identified among RM and non-RM patients. LC boost was delivered to 474 breasts. Fewer (16/43) RM patients received LC boosts compared with non-RM patients (458/607), P = .0001. RM patients were more likely to have neoadjuvant chemotherapy, stage III or multifocal disease, higher body mass index, larger planning treatment volumes, and conventional fractionation (P < .05).

[CONCLUSIONS] RM was associated with decreased use of LC boost without significant differences in acute toxicities. Further investigation to delineate LCs in patients undergoing RM or identify alternative strategies for delivering LC dose is needed.