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

Background: 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.

Aims: The study aims to evaluate the prognostic role of TB in 211 OTSCC patients treated between 1997 and 2018.

Materials & Methods: 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.

Results: 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.

Discussion: 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.

Conclusion: Since the established role of DOI and the poor prognostic value of grading, TB could be considered an independent prognostic marker.