Background: Depth of invasion (DOI) has a significant clinical impact on the staging system of oral squamous cell carcinoma (OSCC). We aimed to compare the prognostic impact of treating DOI as a continuous variable rather than a categorical one.
Methods: A retrospective review of 277 OSCC patients surgically treated in a tertiary care center from 2000 to 2020, with a minimum 2-year follow-up. The analyses were performed using Cox and logistic regression.
Results: DOI as a continuous variable significantly predicted mortality in both univariate (p < 0.001) and multivariate (p < 0.001) analyses. It was also a significant predictor of locoregional recurrence (multivariate p = 0.039) and occult lymph node metastasis (univariate p = 0.005, multivariate p = 0.04). Categorical analysis failed to demonstrate the same significance.
Conclusions: DOI as a continuous factor rather than a categorical one is significantly associated with mortality, locoregional recurrence, and occult lymph node metastasis. This innovative approach promotes personalized risk stratification and better decision-making.
Keywords: depth of invasion; occult lymph node metastais; oral squamous cell carcinoma; overall survival.
© 2024 The Author(s). Head & Neck published by Wiley Periodicals LLC.