Factors Associated With Survival in Complete Pathologic Response Non-Small Cell Lung Cancer.

OBJECTIVES:There is a strong association with improved survival for patients with non-small cell lung cancer (NSCLC) who have developed a pathological complete response (pCR) after neoadjuvant therapy. A national database was used to investigate factors associated with long-term survival in this cohort of patients. PATIENTS:Retrospective review was completed of the National Cancer Database of patients who obtained pCR and had neoadjuvant therapy for stage I to stage III NSCLC between 2004 and 2014. All patients had neoadjuvant chemotherapy with or without radiation therapy. METHODS:Univariate and multivariable analysis was performed on factors associated with overall survival (OS), including gender, clinical stage, and nodal count. Patients were divided into 2 groups based on the Commission on Cancer-recommended median number of lymph nodes (LNs) examined: 0 to 9 LNs and ≥10 LNs. Chi-square and Wilcoxon rank-sum tests were used to compare patient, hospital, and clinical variables between groups. RESULTS:Increased age (hazard ratio [HR] 1.02, 95% confidence interval [CI], 1.00-1.03), neoadjuvant radiation therapy (HR 1.48, 95% CI, 1.10-2.00), and pneumonectomy (HR 1.64, 95% CI, 1.22-2.22) were associated with worse survival in the 759-patient cohort. Multivariable regression demonstrated having ≥10 nodes harvested (HR 0.71, 95% CI, 0.56-0.89) was associated with improved survival as was every increase in LN harvest up to 17 LNs. No significant differences in 5-year OS were found between clinical stage I, II, and III, respectively (66.1% vs. 60.9% vs. 58.6%, P = .288). CONCLUSION:This study shows that younger age, increasing LN harvest, female sex, the absence of neoadjuvant radiation therapy and non-pneumonectomy resections are all associated with improved OS in patients with NSCLC who have developed pCR.