Schwannoma of the breast: report of a case.

This report describes a rare case of a schwannoma that developed in the left breast of a 45-year-old woman without von Recklinghausen's disease. The patient complained of a mass growing slowly in her breast for more than 4 years. She did not have any pain and denied any discharge from her nipple. A physical examination revealed a 3.1 x 2.3-cm, elastic-soft, smooth, and mobile lump close to the nipple of the left breast. Mammography revealed a circumscribed, oval-shaped, and equal dense nodule without microcalcification. On ultrasonography the lesion was found to be a well-demarcated, hypoechoic mass including a large cystic area, which led to the suspicion of a phyllodes tumor. An excisional biopsy was performed. A microcopic examination revealed a structure with interlacing bundles of numerous elongated spindle-shaped cells with a typical palisading pattern. These findings were compatible with schwannoma. A review of the English literature yielded 21 proven cases of breast schwannoma. In this report, we describe another such case and review those documented in the literature.