Fibroepithelioma of pinkus with tumor giant cells.

A case of fibroepithelioma of Pinkus with pleomorphic epithelial giant cells is reported. The lesion was an ovoid polypoid nodule measuring 4 mm x 3 mm x 2 mm and was located close to the right axilla in an 86-year-old woman. The immunohistochemical features of the epithelial giant cells indicate that most of these cells are not cycling. We suggest that these cellular changes may represent a senescent event. Giant cells showed a mean nuclear major diameter more than twice that of small cells. Flow cytometric study of the tumor showed a hypodiploid DNA content and an intermediate grade S-phase fraction of the aneuploid component. To the best of our knowledge, a pleomorphic variant of Pinkus fibroepithelioma has not been reported to date. In fibroepithelioma of Pinkus, the correct diagnosis depends primarily on the architectural pattern of the tumor rather than on its cytologic features.