[Choriogonadotropin measurements--critical assessment of new diagnostic possibilities].

In the human blood and urine there are different antigen forms of choriogonadotropin including nonnicked hCG, nicked hCG, free subunit, free subunit, nicked free, core fragment hCG, hyperglycosylated hCG, nicked hCG missing the subunit C-terminal peptide, asialo hCG, residues 92-145, alternatively nicked hCG--cleaved at 43-44 or 44-45 and others. The authors discuss the value of hCG measurements in the diagnosis of normal pregnancy, pathological pregnancy, Down syndrome screening and oncology: gestational trophoblastic disease, testicular, bladder, digestive tract and other cancers. Special consideration is given to false positive values--phantom hCG--and the consequences of needless therapy.