Trends of Contralateral prophylactic mastectomy at the time of ipsilateral breast tumor recurrence

Background: Contralateral prophylactic mastectomy rates have substantially increased. The study aimed to examine contralateral prophylactic mastectomy (CPM) at the time of ipsilateral breast tumor recurrence (IBTR) and evaluate factors contributing to CPM decision making process. Method: Patients who developed IBTR after BCS from 2011 to 2019 were reviewed. Patient and tumor characteristics, genetic testing and reconstruction details were analyzed. Results: Ninety-six patients had IBTR after BCS and were treated with mastectomy, with 30% electing for a CPM. Patients who underwent CPM were younger, had higher BMI and less comorbidities. A genetic mutation was identified in 19% of patients who underwent testing at the time of IBTR. Tumor characteristics and performing surgeon were not predictors for CPM, however, patients were more likely to undergo CPM if they received reconstruction of the ipsilateral breast with IBTR. Conclusion: This study shows that age, BMI, genetic testing and breast reconstruction are factors contributing to CPM decision at the time of IBTR.