Succinate Dehydrogenase Deficient GIST

Succinate dehydrogenase (SDH), also known as mitochondrial respiratory chain complex II, is located on the inner membrane of mitochondria and consists of four subunits A, B, C, and D [1]. It catalyzes the oxidation of succinate to fumarate in the tricarboxylic acid cycle and participates in electron transfer. The defect of any subunit in SDH complex will lead to the dysfunction of SDH, which results in the accumulation of succinate, abnormal activation of signal pathways related to tumorigenic response and angiogenesis, and promote the occurrence of SDH defect related tumors, of which GIST are the most common. Compared to KIT/PDGFRA gene mutant GIST, SDH deficient GIST presents with particular clinicopathological manifestations, treatment, and prognosis [2].