Five patients with primary malignant mediastinal non-seminomatous germ cell tumours have been treated with a multimodality approach, including cisplatinum-containing chemotherapy, at this institution over the past 7 years. All patients had bulky disease (greater than 10 cm maximum diameter) at presentation and showed raised serum concentrations of human chorionic gonadotrophin or alpha-fetoprotein. Two patients are alive with no evidence of disease at 22 months and 6 years, respectively, from initial diagnosis; two patients have died from progressive disease and one from acute non-lymphocytic leukaemia without evidence of residual germ cell tumour. Long-term survival is achievable for these poor risk patients with a combined modality approach.