[Solving the mystery of non-gestational beta-hCG production: primary choriocarcinoma in the lung].

Choriocarcinoma is a mostly very aggressive, malignant tumor that derives from syncytiotrophoblast cells and secretes beta human chorionic gonadotropin (beta-hCG). Choriocarcinoma is mostly gestational associated with pregnancy and there are rare non-gestational choriocarcinomas, independent of gestation and originated from germ cells mainly occurred extragenitally. Primary choriocarcinoma in the lung is very rare, and its association with kidney metastasis seems to be a literary rarity, as in a 43-year-old woman whose case history and the solving of the hormone-producing tissue of unknown origin is reported here. Histopathological and molecular genetic diagnosis were made on the lobectomy and the nephrectomy specimen. Operative procedures (extirpations of the tumor tissue) and postoperative adjuvant chemo- and immune (antibodies against programmed cell death 1 [PD1] and its ligand [PDL1]) therapy were successfully applied. The patient is being followed up by imaging procedures and beta-hCG measurements. Orv Hetil. 2025; 166(7): 272–275.