YAP1 and neoplasm: Identification of a tumor with the ST-EPN-YAP1 group is based on detection of either YAP1 rearrangement by FISH or one of the YAP1-fusions (YAP1–MAMLD1, YAP1–FAM118B) by RT-PCR, while IHC with anti-YAP1 and/or anti-Claudin-1 is noninformative [19,37].