Survival comparison of Three histological subtypes of lung squamous cell carcinoma: A population-based propensity score matching analysis

Objectives: This study is aimed to analyze the survival differences among patients with lung basaloid squamous cell carcinoma (BSCC), keratinizing squamous cell carcinoma (KSCC), and nonkeratinizing squamous cell carcinoma (NKSCC), and explore the prognostic factors of patients with lung BSCC. Materials and Methods: We searched the information of 4743 patients with lung SCC between 2005 and 2014 from the SEER database. Propensity score matching (PSM) was used to adjust confounding factors. The overall survival (OS), cancer-specific survival (CSS), and cumulative incidence of cancer-specific mortality (CSM) were estimated with a comparative analysis. A competing risks regression model was conducted to identify the prognostic factors of lung BSCC. Results: After PSM, patients with lung BSCC had a higher CSS rate than those with lung KSCC or NKSCC (5-year CSS rate: 50.4 % vs. 37.7 % vs. 38.5 %, p = 0.033 and p = 0.033). The cumulative incidence of CSM was lower for patients with lung BSCC than those with lung KSCC or NKSCC (5-year CSM rate: 46.4 % vs. 56.9 % vs. 56.4 %, p = 0.046 and p = 0.042), which were similar to the results before PSM. As for patients with lung KSCC and NKSCC, there was no survival differences between them (5-year CSS rate: 37.7 % vs. 38.5 %, p = 0.997). The competing risks regression analysis showed that T stage, N stage, M stage and surgery were independent prognostic factors for patients with lung BSCC (all p < 0.05). Conclusions: Patients with lung BSCC had a better survival than those with lung KSCC or NKSCC, while no survival differences were found between lung KSCC and NKSCC. T stage, N stage, M stage and surgery were independent prognostic factors for patients with lung BSCC.