Soft tissue
Fibroblastic / myofibroblastic tumors
Proliferative peribursitis

Author: H. Cliff Sullivan, M.D.
Editor: Jerad M. Gardner, M.D.

Revised: 30 January 2018, last major update June 2013

Copyright: (c) 2002-2018,, Inc.

PubMed Search: Peribursitis

Cite this page: Sullivan, H.C. Proliferative peribursitis. website. Accessed December 13th, 2018.
Definition / general
  • Reactive, angiomyxoid tumor-like mass near joints and ligaments
  • Not a WHO diagnosis
  • Poorly documented in literature
  • Can occur at any age
Clinical features
  • Generally a complication of prior joint disease (e.g. degenerative joint disease, ruptured ganglion cyst), dislocation, or trauma
Microscopic (histologic) description
  • Low power: separate vascular and nonvascular regions; vascular region has cluster of thick vessels, often in nodular pattern, with pericyte cuff in myxoid substance
  • High power: evenly disbursed spindle cells with bipolar and stellate cells and scattered lymphocytes and histiocytes; histiocytes may contain vacuoles and resemble lipoblasts; may have cysts, some resembling ganglion cysts, with or without a synovial lining; occasionally have dense scar
Positive stains
Differential diagnosis
  • Myxoid liposarcoma: uniform round cells, delicate branching "chicken wire" vasculature, scattered uni- or bi-vacuolated monotonous lipoblasts
  • Myxoma: hypocellular, stellate cells only; no prominent vasculature