Poor prognosis of mediastinal germ cell cancers containing sarcomatous components.

Fifteen patients with biopsy-proven mediastinal germ cell tumors treated with platinum-based chemotherapy were reviewed. They had a period of 4 to 6 weeks between the onset of symptoms and diagnosis. Four patients had sarcomatous elements in their tumor in association with common germ cell histologies. The sarcomatous components consisted of one angiosarcoma, one rhabdomyosarcoma, and two cases with mixed angiosarcoma and rhabdomyosarcoma. All patients with sarcomatous elements died; the median survival for these patients was 9 months. In contrast, six (54%) of the patients who did not have sarcomatous elements in their tumor are long-term disease-free survivors 5 to 8 years after diagnosis. The occurrence of sarcomatous elements in a mediastinal germ cell tumor is a poor prognostic sign, and therapy should be oriented to include drugs and regimens that may be effective against sarcoma.