Tumor budding correlates with occult cervical lymph node metastasis and poor prognosis in clinical early-stage tongue squamous cell carcinoma.

BACKGROUND: Tumor budding has been suggested to be a prognostic factor in various human cancers. However, the prognostic value of tumor budding for early-stage (cT1/2N0) tongue squamous cell carcinoma remains inconclusive. This study analyzed the correlation of tumor budding with the clinicopathologic features, and its prognostic significance for cT1/2N0 stage tongue squamous cell carcinoma.
METHODS: One hundred and ninety-five patients with T1/2 stage tongue squamous cell carcinoma enrolled in the retrospective study. Tumor invasive depth, the intensity of tumor budding, and other clinicopathological features were reviewed. Overall survivals were evaluated by the Kaplan-Meier method. For multivariable analysis, Cox's proportional hazards regression models were performed.
RESULTS: The frequency of tumor buds in tongue squamous cell carcinoma is about 85.6% in this study. The intensity of tumor budding showed strong correlations with occult lymph node metastasis (P < 0.05), local relapse (P < 0.01), worse invasive pattern (P < 0.01), and invasive depth (P < 0.05). The invasive depth was significantly associated with T classification (P < 0.01) and lymph node metastasis (P < 0.01). And both high intensity of tumor budding and deeper invasive depth correlated with reduced overall survival. Cox's regression models proved tumor budding to be an independent prognostic factor in clinical early-stage tongue squamous cell carcinoma. Tumor local relapses were also a predictor of tongue squamous cell carcinoma progression.
CONCLUSIONS: Tumor budding is a frequent event in tongue squamous cell carcinoma. It independently predicted prognosis of patients with T1/2 stage tongue squamous cell carcinoma and may be used for routing pathological diagnosis and the decision of elective lymph node dissection.