PDGFRA and gastrointestinal stromal tumor: To investigate possible clinical significance of validated lincRNAs in GIST (validation group n = 22 patients), subphenotype analysis based on histological types (spindle cell type (n = 14), epithelioid cell type (n = 4), mixed spindle and epithelioid cell type (n = 4)), disease risk grade (high (n = 3), moderate (n = 7), low (n = 9) and very low grade (n = 3)) and GIST mutational status (KIT mutant (n = 9), PDGFRA mutant (n = 6), KIT/PDGFRA wild type (n = 2)) was performed (S4 Table).