During the past six years, more than 200 patients were treated with chemotherapy for disseminated testicular cancer with a 70% complete remission rate. In 22 patients who were 17 to 46 years old, there was persistent thoracic disease, which was treated surgically. Six required a median sternotomy for bilateral pulmonary involvement or mediastinal metastasis. In 8 patients, chemotherapy had altered the histological appearance of the metastases from that of an undifferentiated primary tumor to a mature cystic teratoma. Five patients had nodules in the lungs, which were necrotic and fibrosed with no evidence of tumor. Nine showed embryonal cell carcinoma metastases in the lungs. All who had cystic teratoma are alive and free from disease. Three of the 5 with nodules and 1 of the 9 with metastases are currently free from disease. Agressive surgical intervention is important in this unique group of patients in order to determine the precise pathological category of the lesions, to remove intrathoracic malignancy, and to assess the need for additional chemotherapy. An operative mortality of zero and a low morbidity justify this approach.