Ischemic fasciitis: a juxta-skeletal fibroblastic proliferation with a predilection for elderly patients.

We are reporting six examples of a distinctive reactive fibroblastic proliferation occurring predominantly in elderly bed-ridden or convalescent patients that presents as an ill-defined mass often overlying a bony prominence or in close apposition to the periosteum of bone. Unlike conventional fasciitis, the lesion achieves a relatively larger size and is characterized by a biphasic appearance with an outer fringe of mitotically active fibroblasts and capillaries circumscribing a central area of liquefactive and focally coagulative necrosis. Follow-up information in all patients indicated no evidence of aggressive behavior. We believe these lesions arise on an ischemic basis, similar to a decubitus ulcer, from long-standing or intermittent pressure on the soft tissue structures. Because of their large size and close proximity to bone, they are commonly mistaken for a sarcoma.