Is Sarcomatoid Lung Cancer Associated With Inferior Overall Survival? A National Cancer Database Analysis

Abstract

IntroductionSarcomatoid lung cancer has mainly been described in case series and single institution reviews. Although often associated with a poor prognosis, the overall survival compared to other forms of nonsmall cell lung cancer (NSCLC) is unknown. We hypothesize that sarcomatoid lung cancers have worse overall survival relative to other forms of NSCLC. Materials and methodsIn this retrospective cohort study, we identified adult patients with nonmetastatic NSCLC from 2004 to 2018 in the National Cancer Database. Patients were categorized by histology as sarcomatoid, adenocarcinoma, or squamous cell carcinoma. We compared clinical and demographic characteristics between the groups. The primary outcome of overall survival was analyzed using Kaplan-Meier analysis. Multivariable Cox analysis was used to analyze factors associated with overall survival in sarcomatoid patients undergoing surgery. ResultsAmong 1,259,109 patients with lung cancer, there were 5223 (0.4%) sarcomatoid cancers. Sarcomatoid patients were more likely to be male, of Hispanic ethnicity, have fewer comorbidities, and receive treatment at an academic program. Despite higher cT- and M-stages, patients with sarcomatoid cancer were more likely to undergo surgical resection in multivariate analysis (odds ratio = 1.8 [confidence interval 1.60-2.11]; P < 0.001). Among nonmetastatic patients, overall survival was lower for sarcomatoid cancer relative to other histologies in Kaplan-Meier analysis (median survival sarcomatoid 17.6 mo versus nonsarcomatoid 31.5 mo, P < 0.001). ConclusionsThis National Cancer Database study confirms the findings of smaller studies that sarcomatoid cancer is associated with inferior overall survival compared to other NSCLCs. Given the inferior prognosis, further studies regarding optimal staging practices are appropriate.