[Diffuse pigmented villonodular synovitis in the shoulder joint and the biceps tendon: a case report].

Pigmented villonodular synovitis (PVNS) is a benign proliferative disease of synovium frequently most frequently seen in the knee joint and hand tendon synovial tissues; shoulder involvement is extremely rare. It can be seen in joints in two forms as nodular or diffuse involvement. The clinical and radiological symptoms are not specific to the disease and usually mimic other joint diseases. The general complaint of the patients is long-lasting painful swelling that could not be diagnosed. In magnetic resonance imaging it is observed as soft tissue mass. Pigment deposition and histiocytic cell infiltration in the villous synovial projections are the major histological findings. Synovectomy is performed for treatment and the incidence of recurrence is high. In this article, we report a 23-years-old male patient with diffuse PVNS in the shoulder joint and biceps tendon which are rarely involved in PVNS.