MET and neoplasm with perivascular epithelioid cell differentiation: Altogether, the available data clearly indicate the existence of at least two main molecular subtypes of PEComas, with the first subtype consisting of unrestrained activation of the mTORC1 pathway, while the second subgroup presents an elevated transcriptional activity of TFE3 and subsequent induction of pro-oncogenic pathways (c-Met, AKT, mTOR).