The status of the hilar or mediastinal lymph nodes and prethoracotomy carcinoembryonic antigen level were significant independent prognostic factors. Patients with pulmonary metastases potentially benefit from pulmonary metastasectomy even when there is a history of solitary liver metastasis. Careful follow-up is warranted, because patients with recurrent pulmonary metastases can undergo repeat thoracotomy with acceptable long-term survival. Simultaneous bilateral metastasectomy confers no survival benefit. Prospective studies may determine the significance of this type of pulmonary metastasectomy.