Benign granular cell tumor mimicking carcinoma of the breast. Report of a case.

A case of granular cell tumor of the breast in a 59 year-old woman is presented. Clinical evaluation suggested carcinoma with infiltration of the skin. The granular cell tumor was diagnosed on frozen section and the lesion was treated by wide local excision including the overlying skin. Granular cell tumors of the breast, which are usually benign, may closely mimic breast carcinoma, both clinically and on frozen section. The possibility of granular cell tumor of the breast with its potential for a false-positive diagnosis on frozen section supports a two-step procedure for the treatment of breast cancer, especially in young women, to prevent inappropriate radical surgery.