Breast cancer: management of the opposite breast.

Women who have or had cancer in one breast are at especially high risk for developing cancer in the contralateral breast. Other risk factors for second primary breast tumors include age, the use of radiation in treating the index cancer, and pathological characteristics of the original cancer. Management approaches range from close clinical and mammographic surveillance only to immediate prophylactic contralateral mastectomy. Routine and selective biopsy of the opposite breast at the time of treatment of the initial cancer have their proponents. The authors discuss these methods and the effect of a second cancer on overall prognosis.