Cell proliferation is associated with intensity of tumor budding in oral squamous cell carcinoma

BACKGROUND: Tumor budding is a morphological marker of cancer invasion, defined as the presence of isolated or small clusters of neoplastic cells at the tumor invasive front. This study aimed to evaluate the association between intensity of tumor budding and cell proliferation in oral squamous cell carcinoma (OSCC). METHODS: Immunohistochemistry was employed in 163 OSCC samples to detect the cell proliferation marker Ki-67 and multicytokeratin (to identify OSCC cells in tumor budding evaluation). The Mann-Whitney test was used to evaluate differences in the cell proliferation index between samples with high-intensity tumor budding and samples with low-intensity or no tumor budding. In samples with high-intensity tumor budding, the Wilcoxon test was used to evaluate differences in the cell proliferation index between the budding area and the area outside the budding. The chi-square test assessed the association between cell proliferation index and intensity of tumor budding. RESULTS: The cell proliferation index was higher in samples with high-intensity tumor budding than in samples with low-intensity or no tumor budding (P < .05). Tumors with high-intensity tumor budding showed a higher cell proliferation index in the budding area than in the area outside the budding (P < .05). Finally, samples showing high-intensity tumor budding were associated with high cell proliferation index (P < .05). CONCLUSION: Cell proliferation is positively associated with intensity of tumor budding in OSCC. Moreover, in tumors showing high-intensity tumor budding, the budding area is the location of higher cell proliferation. These findings reinforce the hypothesis that tumor budding is associated with the biological behavior of OSCC.