Bilateral risk-reducing mastectomy and reconstruction-A 12-year review of methodological trends and outcomes at a tertiary referral centre.

INTRODUCTION: Bilateral risk-reducing mastectomy (BRRM) involves removal of healthy breast tissue to substantially decrease the risk of developing breast cancer in individuals with greater susceptibility due to a strong family history or genetic mutation. This retrospective study evaluates cases of BRRM and associated reconstruction performed at a tertiary centre, with emphasis on mastectomy and reconstructive trends.

METHODS: A retrospective review of all BRRM cases performed between January 2010 and May 2022 was conducted, with two separate cohorts corresponding to the earlier (group 1) and later (group 2) portion of the time-period. Data collected included demographics, genetic test results, family history of breast/ovarian cancer, co-morbidities, mastectomy type, reconstruction type, surgical histopathology findings and post-operative complications.

RESULTS: A total of 82 patients (group 1 = 41, group 2 = 41) underwent BRRM. The proportion of nipple-sparing mastectomy increased from 14.6% to 56.1% between the two time periods with a reduction in skin-sparing mastectomies from 75.6% to 20.3% (p<0.001). Of the 80 patients who opted to undergo reconstruction, there was a significant decrease in combined flap-implant reconstructions (19.51% to 0%, p<0.01). Importantly, for implant-only reconstruction, there were significant increases in prepectoral approaches (p = 0.0267) and use of acellular dermal matrix (ADM) (48.15% to 90.63%, p<0.001).

CONCLUSION: This study documents recent increases in nipple-sparing techniques for BRRM compared to more traditional skin-sparing methods. Concurrently, reconstruction following RRM has become predominantly implant-based without a flap, coinciding with more widespread usage of ADM. This is consistent with national trends towards fewer complex autologous procedures.