Additionally, use of fluorescence in situ hybridization (FISH) or polymerase chain reaction (PCR) to detect CAMTA1-WWTR1 and YAP1-TFE3 rearrangements can be used as an adjunct to immunohistochemical analysis, tools that are useful in distinguishing epithelioid hemangioendothelioma from other epithelioid vascular neoplasms [10–13]. The gene discussed is WWTR1; the disease is epithelioid hemangioendothelioma.