SDHB and renal cell adenocarcinoma: Rare cases of SDH-deficient renal cell cancers are related to alterations of the SDHA gene: Yakirevich et al. reported a case of SDH-deficiency RCC, characterized by homozygous deletion of the SDHA gene (9 of the SDHA gene exons were deleted): at immunohistochemical level, the expression of both SDHA and SDHB was lost [47].