The lung is the most common metastatic site for all extrapulmonary malignancies except those arising in the portal watershed (1). Pulmonary metastases are found in 30% of autopsy-confirmed fatal neoplasms (2, 3). Up to 20% of patients who die with pulmonary metastases have no other sites of metastasis (3, 4). Pulmonary metastases represent the first recurrence in 50 to 60% of patients with some histologic tumor types, for example, osteogenic and adult soft-tissue sarcomas (5-7). Chemotherapy and radiotherapy for metastatic pulmonary disease is usually palliative, but in such tumors as osteogenic sarcoma and carcinoma of the testes adjuvant combination therapy has reduced the frequency of pulmonary metastases (8). Surgical resection of pulmonary metastases in some selected cases may be the only curative therapy (9-11). However, there have been no prospective randomized studies of pulmonary metastasectomy, and, therefore, it is usually unclear in specific cases whether the procedure will prolong survival or effect a cure. Moreover, effective chemotherapeutic regimens have recently been developed for cancers with a predilection for lung metastasis, but the role of these regimens relative to pulmonary metastasectomy has not been established in prospective trials.
This Clinical Commentary describes principles for selecting patients for resection of pulmonary metastases, prognostic variables, diagnosis of pulmonary metastases, preoperative evaluation, operative technique, and outcome by specific tumor types. We close with a critical commentary on the state of the art of pulmonary resection of tumor metastases.