Risk of Ipsilateral and Contralateral Cancer in BRCA Mutation Carriers with Breast Cancer.

BRCA1 and BRCA2 mutation carriers with breast cancer have a high risk of ipsilateral breast cancer tumor recurrence (IBTR) and a high lifetime risk of contralateral breast cancer (CBC). The IBTR risk is significantly higher in women who elect breast conservation. Oophorectomy has a protective effect for both ipsilateral breast tumor recurrence and CBC. Patients with younger age of breast cancer onset have a significantly greater risk of CBC. Given the higher risk of IBTR and CBC, when indicated, patients with breast cancer should undergo genetic counseling early in their treatment course to assist them in their surgical decision-making. Knowledge of expected outcomes for BRCA1/2 mutation carriers following breast cancer treatment can help appropriately council patients and personalize cancer therapy.