The importance of adjuvant treatment and primary anatomical site in head and neck basaloid squamous cell carcinoma survival: an analysis of the National Cancer Database

Purpose: Basaloid squamous cell carcinoma (BSCC) of the head and neck is an aggressive and highly malignant variant of squamous cell carcinoma that accounts for 2% of head and neck cancers. Previous studies have not analyzed the significance of adjuvant chemoradiation and anatomical site within BSCC subtype and its impact on survival. Methods: A cohort of 1999 patients with BSCC of the head and neck was formed from the National Cancer Database and analyzed with descriptive studies, median survival and 5- and 10-year survival. A multivariable Cox hazard regression was performed to determine the prognostic significance of anatomical site and adjuvant therapy. Results: The most common primary anatomical site was the oropharynx (71.9%) followed by oral cavity (11.5%), larynx (10.1%), hypopharynx (3.5%), esophagus (1.9%), and nasopharynx (1.1%). The presence of metastasis increased the risk of mortality (HR = 2.14; 95% CI 1.40–3.26). Tumors localized to the oropharynx demonstrated better survival compared to all sites except nasopharynx, including the oral cavity (HR = 2.45; 95% CI 1.83–3.29), hypopharynx (HR = 2.58; 95% CI:1.64–4.05), and larynx (HR = 2.89; 95% CI:2.25–3.73). Adjuvant chemoradiation (HR = 0.36; 95% CI 0.23–0.58) and adjuvant radiation (HR = 0.38; 95% CI 0.23–0.64) had better survival outcomes compared to adjuvant chemotherapy. Patients with microscopic margins had better survival outcomes when compared to no surgery (HR = 0.38, 98% Cl 0.23–0.64) while there were no better survival outcomes of patients with macroscopic margins compared to no surgery. Conclusion: This study illustrated that tumors in the oropharynx, lower age, adjuvant chemoradiation and radiation, and microscopic margins were associated with greater survival.