86 unselected patients with poor risk metastatic non-seminomatous germ cell tumours (NSGCT) treated from 1979 to 1990 at a single institution were reviewed with regard to the prognostic relevance of tumour marker analysis. The number of elevated tumour markers was not able to distinguish patients into prognostic subgroups. Pretreatment levels of human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP) and lactate dehydrogenase (LDH) did not have a significant influence on clinical outcome. HCG and AFP half-life analysis during the first chemotherapy cycles also failed to define prognostic subgroups. If early deaths within 90 days after the onset of chemotherapy were excluded, patients with a half-life of HCG decline greater than 3.5 days tended to have a poorer prognosis which did not reach significance.