BREAST-CARCINOMA WITH OSTEOCLAST-LIKE GIANT-CELLS - IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL-STUDY OF A CASE AND REVIEW OF THE LITERATURE

We describe an unusual case of infiltrating ductal carcinoma, not othe rwise specified, containing numerous benign stromal osteoclast giant c ells (OGCs). Macroscopically, the tumor appeared as a well-outlined da rk brown mass and was initially interpreted as a benign lesion on the mammograms. OGCs were uniformly distributed in the tumor and were foun d in vascularized, hemorrhagic stroma often abutted on the nests of tu mor cells. Electron microscopy supported a histiocytic origin of the O GCs, but immunohistochemistry failed to confirm the observation. The p atient was alive and well 30 months following the operation. A review of the literature concerning breast carcinoma with OGCs is also presen ted.