The Impact of Tissue Expander Nipple Asymmetry on Final Implant Symmetry After Bilateral Nipple Sparing Mastectomy

Abstract

Background Asymmetry of nipple position is common in the female population and very difficult to correct after nipple sparing mastectomy (NSM). There are scant data on the impact of tissue expander (TE) nipple asymmetry on final implant nipple symmetry after bilateral NSM. Methods A retrospective review of an institutional review board–approved prospective database of NSM and immediate 2-stage implant reconstruction between June 2014 and December 2019 was performed. BCCT.core software was used to examine TE and final implant nipple asymmetry as well as relative breast implant position. Horizontal and/or vertical asymmetry and breast retraction assessment (BRA) were evaluated. Moderate asymmetry was defined as ≥1 cm and severe asymmetry as ≥2 cm. Lower breast contour ≥1 cm defined implant malposition. Results Twenty-three patients met the inclusion criteria. Linear regression analysis showed a significant relationship between TE BRA and final BRA (R 2 = 0.2321, P = 0.02) with a mean TE BRA of 2.04 and a mean final BRA of 1.53 (P = 0.05). Tissue expander nipple asymmetry was predictive of final BRA score: no TE asymmetry, 0.87, versus TE nipple asymmetry, 1.67 (P = 0.02). Tissue expander lower breast contour ≥1 cm occurred in 8 patients (36.4%) and was associated with implant nipple asymmetry in 7 (87.5%). The second stage of reconstruction significantly improved the nipple asymmetry in those with TE malposition (TE BRA, 2.34, vs final BRA, 1.67; P = 0.05). Two patients who received radiation had increased BRA scores (radiation, 2.14, vs no radiation, 1.47; P = 0.004). Conclusions Tissue expander nipple asymmetry as measured by BRA score or nipple asymmetry was predictive of final nipple symmetry. The second stage of TE reconstruction improves the nipple asymmetry. Final implant exchange can allow for pocket and implant manipulation, improving nipple symmetry. Radiation therapy to TE reconstruction has a negative impact on nipple symmetry after the final stage.