MULTIPLE PRIMARY LUNG CANCERS

Between 1970 and 1990, of 1287 patients undergoing resection for primary lung cancer, we considered 55 (4.3 %) to have a second primary lung cancer, being synchronous in 15 cases (1.2 %) and metachronous in 40 (3.1 %). Two patients had a third primary lung cancer. The 15 patients with synchronous cancers were all treated surgically: ten underwent a two-stage procedure and 5 patients a one-stage. In 6 patients the cancers were located bilaterally and in 4 patients both synchronous cancers had a different histology. There were 3 postoperative deaths (20 %). The 3- and 5-year actuarial survival rates were 26 % and 15 %. Of the 40 patients with metachronous cancers the mean interval between treatment of their first and second cancer was 5 years and 11 months. It was longer for the 21 patients having a contralateral second localization (7 years) than for those having an ipsilateral localization (4 years). There was no dependence of the intervals on whether or not the second cancer had the same histology as the first cancer. In 7 patients the second cancer was treated by chemo- and/or radiotherapie and in 33 patients by surgery. There were 5 postoperative deaths in this group (15.2 %). The 3- and 5-year actuarial survival rates were 33 % and 18 %. For 25 patients with a stage I or II second cancer these rates were 42 % and 27 %; all 8 patients with a stage III second cancer died within 14 months. Survival was positively affected by: histological type differing between both cancers, an interval of more than 3 years, a bilateral localization, and a stage I or II second cancer. In conclusion, a close follow-up including a regular chest radiograph of operated lung-cancer patients is necessary and in case of a new primary lung cancer precise clinical staging; an aggressive surgical approach is indicated in Stage I and II second cancers.