Cell populations involved in pigmented villonodular synovitis of the knee.

Abstract

Our results suggest that preexisting chronic inflammation plays an important pathogenetic role in the PVNS disease process. Chronic inflammation increases the risk of articular bleeding and probably deranges the iron processing capacity of local synovial macrophages. The resulting iron overload could lead to a shift of iron storing cells from synovial macrophages to B synoviocytes and fibroblasts. A perpetuated proliferation and activation of these cells can explain why PVNS behaves like a neoplastic process.