Clinicopathologic predictors of survival in buccal squamous cell carcinoma.

BACKGROUND: Buccal squamous cell carcinoma (SCC) is a locoregionally aggressive malignancy, representing a small subset of oral cancers in North America. We investigated the prognostic value of several clinicopathologic factors in a cohort of patients diagnosed with buccal SCC. METHODS: Between years 1992 and 2017, 52 patients were diagnosed with conventional buccal SCC. Archival surgical pathology material was retrospectively reviewed for reportable findings according to the latest reporting guidelines published by the College of American Pathologists. Clinical data were obtained through chart review. RESULTS: The majority of patients were of older age, current or past smokers, and without specific gender predilection. Most presented at a clinically advanced stage and were treated with surgery alone, or surgery followed by adjuvant radiotherapy. The tumor recurred in about 40% of patients, and almost half of the patients died from the disease by the end of the follow-up period. The worst pattern of invasion (WPOI) was associated with greater depth of invasion (DOI) (p=0.031) and perineural invasion (p<0.001). In univariate analyses, older age (p=0.004), positive nodal status (p=0.047), lymphovascular invasion (p=0.08), perineural invasion (p=0.05) and WPOI-5 (p=0.05) were adverse predictors of 5-year overall survival (OS). In multivariate analysis, older age (p=0.011), WPOI-5 (p<0.001) and perineural invasion (p=0.001) remained statistically significant independent prognosticators of worse 5-year OS. CONCLUSIONS: Older age, WPOI-5 and perineural invasion are significant prognosticators of worse OS. WPOI is associated with DOI, a finding which may have important implications for the pathogenesis and biologic behavior of the disease.