Surgical treatment of metastatic disease to the lung

The presence of distant metastases usually implies disease not amenable to cure through surgical resection. In such cases, chemotherapy is the mainstay of treatment, with surgery or radiation reserved for palliative measures. However, metastases limited to the lung may be resected with resultant prolonged patient survival compared to unresectable, widely disseminated metastases. Isolated pulmonary metastases should therefore not be considered untreatable. In this review, we discuss the pathophysiology of pulmonary metastases. We outline prognostic factors associated with metastases, and propose criteria to help select patients for metastasectomy. Surgical approaches, including various open techniques and video-assisted thoracoscopy, are covered. Surgical issues, including the need for unilateral versus bilateral exploration, the extent of resection to achieve cure, the need for lymph node dissection, and the benefit of repeat operations, are discussed. Finally, we review some of the more common tumors that metastasize to the lungs, and the role of metastasectomy in their treatment. Resection of pulmonary metastases confers a survival benefit to a select group of patients so long as the primary tumor is controlled, metastases are limited to the lungs, the patient can tolerate the operation from a cardiopulmonary standpoint, and the metastases are completely resected.