The SDH-competent tumor group includes: (i) KIT- and PDGFRA-mutated GISTs, (ii) GISTs with mutations in BRAF, NF1, HRAS, NRAS, and (iii) GISTs with exceedingly rare reported mutations in ARID1A, ARID1B, CBL, FGFR1, ATR, LTK, SUFU, PARK2, ZNF217, KRAS, MEN1 and PIK3CA. Additionally, (iiii) GISTs harboring structural chromosomal changes such as FGFR1-HOOK3, FGFR1-TACC1, ETV6–NTRK3, KIT-PDGFRA and PRKAR1B-BRAF are placed within the group of the SDH-competent GIST [9,37,38,39,40,41]. Here, SDHB is linked to gastrointestinal stromal tumor.