The pathophysiology of aberrant mTOR signaling offers a strong rationale to target this pathway and structurally similar mTOR inhibitors, such as sirolimus or everolimus, have shown promising therapeutic activity in PEComas of different sites (Bissler et al., 2008, Wagner et al., 2010, Gennatas and Michalaki, 2012). The gene discussed is MTOR; the disease is neoplasm with perivascular epithelioid cell differentiation.