Malignant Tenosynovial Giant Cell Tumor

**Semantic type:** Neoplastic Process

**Definition:** An uncommon malignant tumor arising from the tendon sheath. Morphologically, it is characterized by the presence of a cellular infiltrate reminiscent of a giant cell tumor with prominent malignant characteristics. Recurrent giant cell tumors with a sarcomatous dedifferentiation are included in this category as well.

**Synonyms:** - Giant cell tumor of tendon sheath, malignant - Malignant Giant Cell Neoplasm of Tendon Sheath - Malignant Giant Cell Neoplasm of the Tendon Sheath - Malignant Giant Cell Tumor of Tendon Sheath - Malignant Giant Cell Tumor of the Tendon Sheath - Malignant Tendon Sheath Giant Cell Neoplasm - Malignant Tendon Sheath Giant Cell Tumor - Malignant tenosynovial giant cell tumor