Furthermore, these FISH assays can be used as an adjunctive method to improve the accuracy of diagnosis for Xp11.2 tRCC, ASPS, PEComas, and other neoplasms that are characterized by a rearrangement of the TFE3 gene and the presence of the ASPL-TFE3 fusion gene. Here, TFE3 is linked to neoplasm with perivascular epithelioid cell differentiation.