ATYPICAL FIBROXANTHOMA - AN UNUSUAL VARIANT WITH OSTEOCLAST-LIKE GIANT-CELLS

We report three cases of an unusual variant of atypical fibroxanthoma with numerous multinucleated osteoclast-like giant cells. Histological ly, the lesions were composed of uniformly dispersed multinucleated os teoclast-like giant cells within a pleomorphic cellular proliferation with microscopic and histochemical features of atypical fibroxanthoma. Multinucleated osteoclast-like giant cells, however, stained with KP- I, a macrophage-associated antigen only. These cells are not necessari ly an integral part of the tumor and may represent a reactive histiocy tic component.