Therapeutic method for early-stage second primary non-small lung cancer: analysis of a population-based database

BACKGROUND: Early-stage non-small lung cancer patients may survive long enough to develop second primary lung cancers. However, few studies have accurately described the therapeutic method, evaluation or prognostic factors for long-term survival in this complex clinical scenario. METHODS: Patients who had first and second primary non-small lung cancer in the Surveillance, Epidemiology, and End Results database between 2004 and 2015 were evaluated. Patients were included when their tumors were pathologically diagnosed as non-small lung cancer and in the early-stage (less than 3 cm and with no lymph node metastasis). Therapeutic methods were categorized as lobectomy, sublobectomy or no surgery. The influence of different therapeutic methods on the overall survival rate was compared. RESULTS: For the first primary tumor, patients who underwent lobectomy achieved superior survival benefits compared with patients who underwent sublobectomy. For the second primary tumor, long-term survival was similar in patients who underwent lobectomy and those who underwent sublobectomy treatment. The multivariate analysis indicated that age, disease-free time interval, sex, and first and second types of surgery were independent prognostic factors for long-term survival. Our results showed that the 5-year overall survival rate was 91.9% when the disease-free interval exceeded 24 months. CONCLUSION: Lobectomy for the first primary tumor followed by sublobectomy for the second primary tumor may be a beneficial therapeutic method for patients. If the disease-free interval exceeds 24 months, the second primary tumor will have no influence on the natural course for patients diagnosed with a first primary non-small lung cancer. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12885-021-08399-y.