Neoteric Predictors for Lymph Node Metastasis in Early Oral Squamous Cell Carcinoma: Tumor Budding and Worst Pattern of Invasion

Oral cancer is one of the most common cancers seen in the Indian subcontinent. Its primary treatment is surgery with or without adjuvant treatment. Despite advances in science, prognosis and overall survival has not yet chanced over the past two decades. Pathologically proven regional lymph node metastasis adversely affects the prognosis. This study was conducted to evaluate the predictive factors for lymph node metastasis in Stage I and II oral squamous cell carcinoma (OSCC) with distinct emphasis on tumor budding and worst pattern of invasion. This is a prospective observational study was done at a tertiary care center, Prince Aly Khan Hospital, Mumbai, over a period of 22 months (March, 2020 to December, 2021). We analyzed 237 patients of early OSCC for clinicopathological parameters (age, trismus, differentiation, depth of invasion, tumor budding, worst pattern of invasion). Chi Square test and logistic regression model were used for data evaluation. Statistical Package for Social Sciences, version 21.0 IBM Corporation USA for Microsoft Windows, was used for data analysis. This study reported statistically significant predictive factors for lymph node metastasis viz. tumor budding (OR 30.8 95% CI 12.365-76.731 p < 0.001), worst pattern of invasion (OR 4.5 95% CI 1.853-11.305 p = 0.001) and age (OR 0.149 95% CI 0.043-0.0516 p < 0.003) on logistic regression model. On Chi square test, along with the above factors- tumor differentiation (p = 0.008) and depth of invasion (p = 0.001) were also found statistically significant in prediction for lymph node metastasis in early OSCC. Strong predictive association exists between lymph node metastasis and tumor budding, worst pattern of invasion and higher age group in early OSCC. These factors can be adapted as a routinely assessed predictive marker and mentioned in histopathology reports with its prognostic implications, thus can be considered for further planning and management. These predictive factors can be used to formulate a risk score to incorporate various clinicopathological factors including tumor budding, worst pattern of invasion, depth of invasion, tumor differentiation and T stage which can be used in patients diagnosed with early stage I & II OSCC where neck dissection can be avoided.