HCG

HCG is a glykoprotein hormon, 38 kDa, produced in large amounts by placental syncytiotrophoblast cells. It consists of a specific ?-chain and a ?-chain common for several polypeptide hormones. Outside the placenta HCG has been demonstrated in some pituitary cells and in reactive gastrointestinal epithelium.

HCG is found in moles and choriocarcinoma, chorionic components of germ cell tumours, and syncytiotrophoblast like cells in seminoma/dysgerminoma and embryonal carcinoma. ”Ectopic” HCG may be demonstrated in carcinomas like adenocarcinomas of the gastrointestinal tract, prostate, breast and small cell carcinoma, as well as carcinoid tumour and hepatocellular carcinoma.

Classification of germ cell tumours, identification of extragonadal germ cell tumours.

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