From 1970 to 1993, 155 thoracotomies for metastatic lung tumors were performed on 113 patients in the Department of Surgery, Kanazawa University School of Medicine. Overall 30-day mortality amounted to 0.9% (1/113). The cumulative 3- and 5-year survival rates were 39.4% and 29.1%, respectively. The overall median survival was 24 months. The 5-year survival rate for carcinoma was 37.2% and for sarcoma it was 14.5% (P < 0.01). The other significant predictors of better long-term survival with metastatic lung tumors were solitary lesions, disease-free interval (DFI) > 24 months, and tumor size < or = 20 mm in diameter. There was no significant difference in survival based on the method of pulmonary resection. Repeat thoracotomy for recurrent metastases was performed in 27 patients, whose 5-year survival rate after the first lung resection was 35.5%. For bilateral pulmonary metastases, we recently performed simultaneous bilateral thoracotomy via median sternotomy on 25 patients and transsternal simultaneous bilateral thoracotomy on 8 patients. The latter procedure provides a wide operative field and better survival. We conclude that resection of metastatic lung tumors is safe and effective, and that repeat thoracotomy is warranted in selected patients with recurrent pulmonary metastases.