Abstract Purpose This study aims to explore prognostic factors for late cervical lymph node metastasis in oral tongue squamous cell carcinoma (OTSCC) with pathological depth of invasion (pDOI) ≤ 3 mm, which, despite shallow invasion, may still be associated with unfavorable oncological outcomes. We emphasize tumor budding (TB) as a potential risk indicator. Methods We retrospectively analyzed 107 patients with pT1–T2N0 OTSCC and pDOI ≤ 3 mm. Variables associated with late cervical lymph node metastasis were first evaluated using univariate analysis. Significant factors were then tested in a multivariate Cox proportional hazards model. We also assessed whether combining pDOI and tumor budding (TB) improved predictive performance. Results Neck recurrence occurred in nine patients (8.4%) within 3 years. Multivariate analysis identified TB ≥ 5 as an independent prognostic factor for late cervical lymph node metastasis. The combination of pDOI ≥ 2.0 mm and TB ≥ 5 improved sensitivity and negative predictive value for identifying high-risk cases. Conclusion In OTSCC with shallow pDOI (≤ 3 mm), TB is a significant prognostic factor for late cervical lymph node metastasis. Incorporating TB into routine pathological evaluation may improve risk stratification in early-stage cases and inform postoperative surveillance strategies.
Yonaga et al. (Wed,) studied this question.