Fragments of synovial tissue composed of variably preserved synovial lining and underlying stroma. There is recent and organizing hemorrhage with clotted blood and layered fibrin. The synovial lining is focally hyperplastic. There is a variable chronic inflammatory infiltrate composed predominantly of lymphocytes and plasma cells, with scattered macrophages. Areas of granulation tissue with neovascularization and fibroblastic proliferation are seen, with focal fibrosis. No cellular atypia, necrosis, or true villonodular neoplastic proliferation is identified.
Known case of thalassemia presented with knee swelling.
Soft tissue fragment measured 1.5x1x0.5 cm, totally embedded.
Knee swelling, biopsy: