Coexistence of granular cell tumor and ipsilateral infiltrating ductal carcinoma of the breast.

Granular cell tumor is a benign neoplasm that is rarely seen in the breast and can mimic carcinoma, both clinically and by gross pathologic examination. The coexistence of a granular cell tumor with a primary mammary carcinoma can potentially pose diagnostic and therapeutic problems. In this report, we document a granular cell tumor of the breast coexisting with an ipsilateral infiltrating ductal carcinoma in a 74-year-old woman and discuss its clinical significance.