Tumor Location and Survival Outcomes in Lung Adenosquamous Carcinoma: A Propensity Score Matched Analysis

BACKGROUND There is little information in the literature available on lung adenosquamous carcinoma (LASC). The association between tumor location and survival outcomes in LASC is poorly understood. Our study was designed to probe the effect of tumor location on survival outcomes of LASC. MATERIAL AND METHODS Patients with LASC between 2004 and 2015 were identified using the Surveillance, Epidemiology and End Results (SEER) databases. The patients were divided into 2 groups, a main bronchus group and a peripheral group, according to their primary sites. The Propensity Score Matching (PSM) method was used to reduce possible bias between groups. The primary endpoints were overall survival (OS) and cancer-specific survival (CSS). RESULTS A total of 3176 patients, afflicted with LASC between 2004 and 2015, were extracted from the SEER databases. Of these, 212 patients were found to be eligible for analysis after a propensity 1: 1 nearest neighbor matched analysis. After PSM, multivariate Cox regression analysis showed that primary site, American Joint Committee on Cancer (AJCC) stage, T stage and surgery were independent predictors of LASC in both OS and CSS. Kaplan-Meier survival analysis showed that patients with LASC located in a peripheral site had better survival outcomes than those with LASC located in the main bronchus. In subgroup analysis, the advantages of tumor located in a peripheral site were more pronounced in female patients and AJCC stage I patients. CONCLUSIONS Tumor location may have an impact on the survival outcomes of patients with LASC. Patients with LASC located in a peripheral site had better survival outcomes than patients with LASC located in the main bronchus, particularly in female patients and AJCC stage I patients.