Primary epithelioid trophoblastic tumor of the lung: A case report.

Primary epithelioid trophoblastic tumor (ETT) of the lung is exceedingly rare. Only about three cases have been reported in Pubmed and worldwide literature. We presented a case of multiple primary ETT of the lung occurring in a 33-year-old Chinese female patient. Comprehensive physical examinations revealed no evidence of a primary lesion on the uterus or cervix uteri. Microscopic examination of the tumor demonstrated ETT of the lung, which was confirmed by immunohistochemical staining and declining level of beta-human choriogonadotropin (β-HCG) after the operation. Our case revealed that the ETT can occur in the lung and should be considered when a female had a tumor of lung with increasing β-HCG.