TSC1 and neoplasm with perivascular epithelioid cell differentiation: The tumor group of the PEComa family may be related to genetic alterations of the tuberous sclerosis complex (TSC), an autosomal dominant genetic disease due to loss of function mutations in the TSC1 (9q34) or TSC2 (16p13.3) genes, which play a role in the regulation of the Rheb/mTOR/p70S6K pathway (1,6,9).