While morphologic examination or immunohistochemical profiling often allow pathologists to accurately diagnose gestational trophoblastic neoplasms, screening of GTD samples for TERT expression or the presence of the LPCAT1-TERT fusions (either RNA or protein) may offer greater diagnostic certainty in differentiating ETT from histologically similar lesions, especially when immunohistochemical markers overlap. The gene discussed is TERT; the disease is gestational trophoblastic neoplasm.