TFE3 gene rearrangment by FISH assay and moderate to strong nuclear TFE3 positivity by IHC are virtually pathognomonic for ASPS, Xp11.2 translocation associated RCC [19], and a subset of PEComa that harbors TFE3 gene fusion [20]. This evidence concerns the gene TFE3 and neoplasm with perivascular epithelioid cell differentiation.