SDHB and gastrointestinal stromal tumor: Germline or epigenetic alterations of SDH are found in approximately 5.10% of GIST and are associated with particularly aggressive tumors that have an early onset, poor prognosis, and a poor response to conventional therapies compared to GIST with pathogenic variants in the KIT proto-oncogene, and platelet-derived growth factor receptor alpha (PDGFRA) genes [131].