Metastatic epithelioid trophoblastic tumor of the lung: A case report

RATIONALE: Epithelioid trophoblastic tumor (ETT) is a very rare form of gestational trophoblastic disease (GTD) which arises from neoplastic proliferation of intermediate trophoblasts. Metastatic ETT of the lung is extremely rare in postmenopausal women. PATIENT CONCERNS: Here we describe a 50-year-old woman with a metastatic ETT of the lung showing increasing tracer uptake at PET/CT. DIAGNOSIS: Hematoxylin–eosin staining showed a tumor composed of nests of epithelioid cells with necrotic debris and peritumoral hyaline-like material. Immunohistochemical staining of the tumor cells was positive for human chorionic gonadotropin (HCG) and cytokeratin 18. INTERVENTIONS: The patient underwent thoracoscopic lower left lobectomy combined with mediastinal lymphadenectomy. At surgery, a solid mass (size 3.0 × 3.0 cm) was found in the left lower lung. OUTCOMES: The patient was discharged on the tenth day postsurgery, following an uneventful recovery. Three months postsurgery, the patient was asymptomatic and is currently being managed with close follow-up. LESSONS: Metastatic ETT of lung is a very rare disease. Complete surgical resection and chemotherapy may be the critical therapeutic option.