Comparative Analysis of Clinical, Treatment, and Survival Characteristics of Basaloid and Squamous Cell Carcinoma of the Esophagus

Background: Basaloid squamous cell carcinoma (BSC) is a rare variant of squamous cell carcinoma (SqCC) of the esophagus. Even though pathologically thought to be more aggressive than SqCC, there is discrepancy in the literature regarding the outcomes of BSC compared with those of SqCC. Study Design: We conducted a retrospective cohort study using the Surveillance Epidemiology and End Results (SEER) database. All patients with a histologic diagnosis of BSC and SqCC between 2004 and 2013 were included. We compared treatment and survival characteristics of patients with BSC and SqCC. Results: There were 16,158 patients included in this study; 173 patients (1.1%) had BSC. There were no significant differences between the 2 groups based on age, sex, marital status, insurance, or geographic region of diagnosis, but patients with BSC were more likely to be Caucasian (73.4% vs 64.7%; p = 0.017). Among staged patients, baseline tumor stage was similar in both groups. However, BSC tumors were more likely to be of high pathologic grade (56.8% vs 38.2%; p < 0.001). Patients with SqCC were more likely to receive radiation therapy (36.9% vs 53.9%; p < 0.001), while patients with BSC were more likely to undergo resection (32.4% vs 17.0%; p < 0.001). Median overall survival was similar in both groups (14 vs 9 months; log rank = 0.144), and this relationship persisted after stratification by treatment. Conclusions: Even though more likely to be poorly differentiated at presentation, BSC of the esophagus seems to have similar clinical features and survival outcomes when compared with SqCC. Patients with BSC and SqCC should undergo stage-specific treatment to achieve optimal outcomes.