Therapeutic Options For Resectable Second Lung Tumor After Previous Pneumonectomy: A Seer Database Analysis

Background: Therapeutic options for patients with second lung tumor (SLT) after previous pneumonectomy for lung cancer are sparsely reported and controversial. This study aims to compare the short-and long-term outcomes of different treatment patterns in patient with resectable postpneumonectomy SLT.Methods: Patients received previous pneumonectomy and subsequently occurred resectable SLT were extracted from the Surveillance, Epidemiology, and End Results (SEER) database [1998-2016]. Treatment related mortality was compared using the Pearson chi-square test. Univariate and multivariate Cox regression analyses were performed to identify the independent prognostic factors for cancer-specific survival (CSS) and overall survival (OS).Results: Ninety-nine patients met the selection criteria with 5-year CSS and OS rates of 60.8% and 53.7%, respectively: 23 patients received no lung resection (nLR) and 76 patients received lung resection (LR). There was no statistically significant difference between nLR group and LR group in both treatment related mortality (0.0% vs. 2.6%, P=0.432), CSS (58.3% vs. 61.7%, P=0.633) and OS (55.3% vs. 53.3%, P=0.635). Patients with subsequent adenocarcinoma (P=0.001) and smaller tumor size of SLT (P<0.001) were more likely to receive LR treatment. In the LR subgroup analysis, patients received sublobar resection (SLR) had better CSS [hazard ratio (HR): 0.381, 95% confidence interval (CI): 0.176-0.827, P=0.030] and OS (HR: 0.562, 95% CI: 0.287-1.100, P=0.051) than those received lobectomy.Conclusions: SLR or non-surgical resection is reasonable therapeutic option for patients with resectable SLT after previous pneumonectomy to achieve long-term survival, with acceptable treatment related mortality.