Integrative genomic characterization and a genomic staging system for gastrointestinal stromal tumors

Abstract

Background: Gastrointestinal stromal tumors (GISTs) historically were grouped with leiomyosarcomas (LMSs) based on their morphologic similarities; however, recently, GIST was established unequivocally as a distinct type of sarcoma based on its molecular features and response to imatinib treatment. Methods: To gain further insight into the genomic differences between GISTs and LMSs, the authors mapped gene copy number aberrations (CNAs) in 42 GISTs and 30 LMSs and integrated the results with gene expression profiles. Results: Distinct patterns of CNAs were revealed between GISTs and LMSs. Losses in 1p, 14q, 15q, and 22q were significantly more frequent in GISTs than in LMSs (P