Disease Recurrence and Second Tumors in Long-term Survivors of Lung Cancer.

INTRODUCTION AND OBJECTIVES: As cancer survival improves, the appearance of multiple tumors in a single patient is becoming more common. The aim of this study was to analyze long-term evolution, focusing particularly on disease recurrence and second primary tumors, in patients with lung cancer (LC) and ≥ 3 years overall survival. MATERIAL AND METHODS: Retrospective study of 1,769 patients with LC. A total of 218 (136 treated with surgery and 82 with other treatments), followed up for between 5 and 23 years were enrolled. LC progress and intercurrent diseases were recorded. RESULTS: A total of 65 patients presented tumor relapse, of which 60.9% occurred in the first 3 years; 26 patients developed secondary primary tumors (84.6% after 5 years) and 24 developed 2 or more second extrapulmonary tumors (66.6% after 5 years), most of which were smoking-related. The incidence of second primaries was greater than the expected incidence of cancer in the general population matched for age and sex. CONCLUSION: The multiple carcinogenic effect of smoking persists and manifests in various organs, more than 5 years after the diagnosis of LC, even in patients with long survival. After 5 years, a second tumor is more likely than a relapse of the primary disease, and the lung is the most common site of development of a second tumor.