Second lung cancers in patients successfully treated for lung cancer.

The rate of developing second lung cancers and other aerodigestive tumors in patients who have been treated for both small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) is approximately 10-fold higher than other adult smokers. The risk of second lung cancers in patients surviving resection of NSCLC is approximately 1% to 2% per year. The series reported show that the patients who develop second NSCLCs tend to have early-stage NSCLC (predominantly stage I and II). The survival of patients after the second resection of lung cancer is similar to that of patients presenting with initial NSCLC. The risk of second lung cancers in patients surviving SCLC is 2% to 14% per patient per year and increases two- to seven-fold with the passage of time from 2 to 10 years. The risk of second lung cancers in patients treated for SCLC appears to be higher than that found in patients with NSCLC who were treated only with surgical resection. In addition, the chances of successful resection of second primary NSCLCs in patients who were treated for SCLC is much less than that for patients with metachronous lung cancers after an initial NSCLC. Patients treated for SCLC who continue to smoke cigarettes increase their rate of developing second lung cancers. The contribution of chest radiation and chemotherapy administration to the risk of developing second lung tumors remain to be defined but may be responsible for some of the increased risk in patients treated for SCLC compared to patients undergoing a surgical resection for NSCLC.