SMAD4 and neoplasm: Moreover, several tumor suppressors (CDKN2A/B, CDKN1B, CDKN2C, ARID1A, KIF1B, SMARCB1, PTEN, DMD, LATS2 and SMAD4) and oncogenes (CCND2, KRAS, BRAF, ETV1, EGFR, MYCN, SMO and TERT) were found recurrently altered in metastatic GIST specimens and rarely in localized tumors.