Tenosynovial giant cell tumour

Tenosynovial giant cell tumor (TGCT) is a non-malignant tumor defined histologically as inclusions of "osteoclast-like" multinucleated giant cells, hemosiderin, and macrophages. This histology can present one of 2 clinically distinct ways. Localized/nodular TGCT (L-TGCT), sometimes referred to as "giant cell tumor of the tendon sheath"; is a common tumor that presents as a slow-growing, encapsulated, localized and limited bump, most frequently in the fingers. Diffuse TGCT (D-TGCT) — also called pigmented villonodular synovitis (PVNS)— is a rare tumor that presents as a proliferative, destructive, intra-articular lesion, most commonly in the knee. D-TGCT tumors often develop from the lining of joints (also known as synovial tissue).. Common symptoms of D-TGCT include swelling, pain, stiffness and reduced mobility in the affected joint or limb.

Underlined words are explained — tap any of them.