Pulmonary resection for metastatic disease in 341 patients resulted in a cumulative survival rate of 36.6% at 5 years and 26.6% at 10 years with an operative mortality of 0.9%. 5-year survival rate was 44.3% in colorectal carcinoma (n = 85), 36.2% in cervical cancer of uterus (n = 35), 40.6% in renal cell carcinoma (n = 32), 50.3% in breast cancer (n = 23), 50.0% in testicular cancer (n = 16), 17.9% in osteosarcoma (n = 33), 34.1% in soft part sarcoma (n = 38). The patients with resected metastatic pulmonary lesions from colorectal and renal cancer showed a good 5-year survival, and then the survival decreased gradually. On the other hand, the survival for testicular and breast cancer, osteosarcoma and soft part sarcoma decreased rapidly in the first 2 to 3 years, but a plateau was reached. Each primary malignancy should be analyzed individually because of the differences of their biologic behaviors. Significant factors influencing survival were (1) patients selection for pulmonary resection, (2) the biologic growth rate of each primary malignancies, and (3) effectiveness of chemotherapy for primary malignancies. Presumably, a good 5-year survival rate after thoracotomy would be a reflection of a length bias, caused by the biologic behavior of the metastatic pulmonary disease. The true benefit for the surgical approaches to metastatic neoplasm of the lung are still controversial.