[Atypical decubital fibroplasia (ischemic fasciitis)--a new pseudosarcomatous entity]

Two cases of atypical decubital fibroplasia (ischemic fasciitis) were presented. Both patients were immunocompromized and their lesions were located in usual decubital places (back shoulder, femorogluteal region). Histology was typical: 1. zone of fibrinoid necrosis, 2. neighbouring cellular parts reminding of proliferative fasciitis. Focal high cellularity with atypical ganglioid fibroblasts and mitotic activity imitated sarcoma. Immunohistochemistry showed expression of vimentin in all cells and of KP1 (CD 68), lysozym as well as F-XIIIa in majority of them. There was not any expression of desmin, actin, S-100 protein, cytokeratin and epithelial membrane antigen. Importance of atypical decubital fibroplasia (ischemic fasciitis) is in its histological similarity to sarcoma-as it was in both the presented cases.