Prognostic significance of tumor budding thresholds in oral tongue squamous cell carcinoma

Oral tongue squamous cell carcinoma (OTSCC) represents the most common malignancy of the oral cavity. Tumor budding (TB) is a reliable prognostic factor in OTSCC; however, a standardized scoring system is not still validated.The study aims to evaluate the prognostic role of TB in 211 OTSCC patients treated between 1997 and 2018.TB was evaluated on hematoxylin and eosin-stained sections in the hotspot area of the infiltrative front (×200-magnification). It was scored using a two-tier system, a three-tier system, and according to BD-model and revised-Grading system. Univariate and multivariate Cox regression analyses of disease-specific survival (DSS) and disease-free survival (DFS) were performed. A p < 0.05 was considered as statistically significant.The two-tier and three-tier systems resulted an independent prognostic factor of DSS. High-risk patients had a 2.21 and 3.08 times increased probability of poor DSS compared with low-risk group. It is significantly increased even for intermediate-risk group. No significant differences emerged classifying patients according to BD-model and revised-Grading system.These data confirm the prognostic value of TB in predicting DSS in OTSCC. Classifying patients into two groups using the 5-bud cutoff significantly discriminates their outcomes.Since the established role of DOI and the poor prognostic value of grading, TB could be considered an independent prognostic marker.