SOLITARY FIBROUS TUMOR OF THE PERIOSTEUM

We report a solitary fibrous tumor (SFT) of the leg that presented as a pedunculated encapsulated soft tissue mass attached to the periosteu m of the posterior tibia. To our knowledge this is the first reported case of an SFT in an extremity. In addition to having the typical gros s and microscopic appearance of a usual SFT, this SFT also contained a bundant elastic tissue, suggesting an origin from periosteal fibroblas ts. This report further extends the anatomic range of the SFT, a neopl asm once thought to be of mesothelial origin but now recognized as a m esenchymal tumor of probable fibroblastic lineage. To date the behavio r of the this periosteal SFT has been benign. HUM PATHOL 26:460-462. C opyright (C) 1995 by W.B. Saunders Company