PROLIFERATIVE FASCIITIS - REPORT OF A CASE WITH HISTOPATHOLOGIC AND IMMUNOHISTOCHEMICAL STUDIES

We present a case of proliferative fasciitis arising adjacent to an op erative scar of the right lower leg of a patient with chronic lymphati c leukemia, diabetes mellitus, and multiple subcutaneous angiolipomas. A 61-year-old man had a hard mass in his right lower leg that had rap idly increased in size in the past 10 days. The mass was microscopical ly composed of a dense proliferation of spindle cells forming interlac ing fascicles admired with an inflammatory infiltrate of lymphocytes a nd eosinophils, focal hemorrhage, and myxomatous change as typically s een in nodular fasciitis as well as many characteristic ganglion cell- like giant cells. Immunohistochemically, most of the spindle-shaped ce lls were positive for vimentin and alpha-actin, whereas the ganglion c ell-like giant cells were positive for vimentin and negative for alpha -actin and lysozyme. We suggest that the main component cells of proli ferative fasciitis are fibroblastic in nature, many of which an myofib roblasts in large part, whereas the ganglion cell-like giant cells are related more closely to fibroblasts rather than histiocytes or pericy tes. Additionally, proliferating cell nuclear antigen (PCNA) stain rev ealed that many of the fibroblastic cells showed high proliferative ac tivity, especially in the hypercellular areas, although there was no s ignificant difference in PCNA staining between the focus traumatized b y the needle biopsy and the nontraumatized areas.