Primary hepatic metastatic epitheloid trophoblastic tumor of the uterus treated with multimodal therapy including pembrolizumab and thermoablation. Case report of an extremely rare disease and review of the literature

Epithelioid trophoblastic tumor (ETT) is a rare gestational trophoblastic tumor, first described by Shih and Kurman in 1998. ETT often present as abnormal vaginal bleeding in women of reproductive age, but unlike more common forms of GTN tend to produce much less human chorionic gonadotropin (hCG) for the volume of disease present. ETT can occur after any gestational event and can occur in both intrauterine and extrauterine sites. We present a case of a 46-year-old female patient incidentally diagnosed with ETT and hepatic metastasis. Therapy was multimodal and involved chemotherapy, operation, thermoablation of liver metastases and immunocheckpoint inhibitor. The patient remains disease free for almost four years now. ETT presents a diagnostic challenge due to their rarity and histologic resemblance to other pathologies. ETT can be relatively chemo resistant and are therefore often treated surgically. Misdiagnosis might delay effective treatment and affects survival.