Testicular germ cell tumours (GCT) are highly curable though require proper management at all stages. GCTs are classified in two major subgroups: seminoma and non-seminoma. Sérum concentrations of tumour mar-kers - AFP, LDH and beta-HCG - are an integrál part of the TNM classification systém as the S category. Independent prognostic factors for progression-free survival for patients with GCT include pre-treatment le-vels of LDH, HCG and AFP, site of primary tumour (i.e. mediastinal vs. testis or retroperitoneal) and the presence of non-pulmonary visceral metastases (such as bone, brain or liver metastases). We describe representative dynamics of tumour marker levels in 4 patients with advanced GCT. Careful periodic check-ups are required following radiotherapy (for clinical stage I, IIA and IIB seminoma) and after chemotherapy (III stage seminoma, non-seminoma tumours) - which consist of chest X-ray, abdominal CT scan, PET scan, determination of sérum concentration of AFP, HCG, LDH and a physical examination. An abnormal marker sérum concentration may indicate latě relapse.

        Key words: germ cell tumour, seminoma, non-seminoma, tumour marker, TNM classification.