Occurrence of malignant non-germ cell components in primary mediastinal germ cell tumours.

METHODS: Thirty-five patients with primary mediastinal germ cell tumours (PMGCT) underwent primary thoracotomy in a 30-year period (1965-1994). Of the 35 patients, 12 had benign teratomas, five pure seminomas and 18 non-seminomatous germ cell tumours. RESULTS: Out of 18 non-seminomatous germ cell tumours, 14 comprised more than one malignant component. In two cases malignant teratomas had an additional malignant non-germ cell component: one a mixed sarcomatous component and the other a neuroendocrinal component. There were different methods of treatment between 1965 and 1994. All but one of patients with seminomas survived for 5 years. Among 18 patients with malignant PMGCT, all but two died within 5 years (mean survival rate was 15 months). CONCLUSIONS: When planning treatment of patients with malignant PMGCT we have to take into account the fact that malignant non-germ-cell components may occur. In this circumstances, surgical resection after initial chemotherapy is recommended.