Utilization of fluorescence in situ hybridization in the diagnosis of 230 mesenchymal neoplasms: an institutional experience.

Abstract

Abstract Context—Mesenchymal neoplasms harbor characteristic translocations and amplification of gene regions amenable to evaluation by fluorescence in situ hybridization (FISH). Objective—To determine the utility of FISH in the diagnosis of mesenchymal neoplasms. Design—Two hundred thirty soft tissue cases analyzed by FISH were reviewed retrospectively. Results—Morphologic patterns where FISH was used included high-grade round cell sarcomas (n = 67), nonmyogenic spindle cell sarcomas (n = 40), low-grade myxoid neoplasms (n = 34), adipocytic neoplasms (n = 20), and melanocytic neoplasms (n = 19). Fifty cases did not fit into the previously mentioned categories. SYT FISH (96% of monophasic synovial sarcomas were positive; 0% of malignant peripheral nerve sheath tumor were positive) and DDIT3 FISH (100% of myxoid/round cell liposarcomas; no other neoplasm positive) were very sensitive and specific. EWSR1 FISH was very sensitive and specific in the differential diagnosis of melanocytic neoplasms (8...