label: NTRK-Rearranged Spindle Cell Neoplasm
label_lc: ntrk-rearranged spindle cell neoplasm
description: "An emerging rare group of soft tissue tumors, usually characterized by a monomorphic spindle cell infiltrate, stromal hyalinization, and frequent coexpression of S100 and CD34 by immunohistochemistry. Most tumors harbor NTRK1 fusions with a variety of partners. Rare cases involving NTRK2 and NTRK3 fusions have also been reported."