Succinate dehydrogenase B (SDHB) is an iron-sulfur component of mitochondrial complex II, which is a respiratory enzyme that facilitates the oxidation of succinate within the mitochondrial membrane. Various cancers often show positive results for SDHB, such as renal cell carcinomas (RCC) and gastrointestinal stromal tumors (GIST). Nevertheless, a group of RCC and GIST tumors linked to SDH mutations, Carney-Stratakis Syndrome, or Carney Triad display a reduction in SDHB expression.