Tumor budding is associated with poor prognosis of oral squamous cell carcinoma and histologically represents an epithelial-mesenchymal transition process.

In this study, we aimed to identify whether tumor budding is associated with the progression and prognosis of oral squamous cell carcinoma (OSCC) and investigate the correlation between tumor budding and regulators of epithelial-mesenchymal transition (EMT). Fifty-six cases of OSCC were selected and their tumor budding status was reviewed using archived hematoxylin and eosin-stained slides. In addition, the expression of EMT regulators was evaluated by immunohistochemistry using antibodies against Snail and Twist. Tumor budding was observed in 19 (33.9%) of the 56 cases of OSCC. Tumor budding was strongly associated with lymph node metastasis (P = .001) and shorter overall survival (P = .002). The expression of Snail and Twist was correlated with lymph node metastasis (P < .001 and .002, respectively) and poorer overall survival (P = .024 and .024, respectively). Tumor budding was significantly associated with the expression of Snail (P = .003) and showed a tendency toward higher expression of Twist (P = .08). Therefore, our results suggest that tumor budding is significantly associated with poor prognosis in patients with OSCC and histologically represents an EMT process in OSCC.