From January 1979 to December 1988, 18 patients with pulmonary metastases from colorectal cancers were operated in our division. This series included 11 men and 7 women (average age 57 years). The primary cancer was colic in 6 cases and rectal in 12. In 3 cases, the metastases were synchronous and discovered during the initial assessment. In 15 cases, they were metachronous, without symptoms in 12 cases and symptomatic in 3. These metastases were single in 14 cases, multiple in 3, bilateral in 1. They were peripheral in 15 cases. The histological diagnosis was obtained preoperatively in 5 cases (27.7%). The procedures uses were lobectomy for 11 patients, segmentectomy for 1, wedge resection for 10. Postoperative chemotherapy was given to 7 patients. Benign complications occurred in 2 cases during the postoperative period. No perioperative death was noted. One patient was lost to follow-up without recurrence after 1 year, 6 patients died from neoplastic evolution 4, 8, 15, 17, 22 and 28 months after being operated. In May 1989, 11 patients were still living: -2 scheduled for the excision of a contralateral lesion, -2 with pulmonary recurrence. 7 patients were alive without recurrence 12, 14, 17, 46, 52, 68 and 108 months after being operated. The probability of occurrence of pulmonary metastases in the evolution of colorectal cancer is estimated between 20 and 50%. Only 1% of the patients can be treated surgically. When screening these lesions, one must bear in mind that their appearance is sometimes quite delayed, and often asymptomatic. The repeated use of tracers is necessary but not sufficient.(ABSTRACT TRUNCATED AT 250 WORDS)