Objective: To identify the effects of clinical and histopathological parameters on neck metastasis in early-stage oral cavity cancers.

Methods: The medical records of 92 patients who underwent primary surgical resection and concurrent neck dissection due to early-stage oral cavity squamous cell cancer at ‹zmir Atatürk Training and Research Hospital between June 2001 and June 2010 were retrospectively reviewed. The associations of clinical and histological parameters with neck metastasis were assessed. Based on the histological data, the histological sections of the operative tissue were obtained via the measurement of tumor width and tumor depth. Using an optical micrometer, the maximum width at the horizontal plane and the maximum depth at the vertical plane were measured and the maximum depth was recorded as tumor thickness.

Results: The association between neck metastasis and tumor localization, T stage, degree of differentiation, tumor thickness, perineural invasion, vascular invasion and perilymphatic invasion in early-stage oral cavity cancers was found statistically significant (p<0.05). The value of critical tumor thickness for the neck metastasis was found to be 5.6 mm.

Conclusion: On the basis of our results, a tumor thickness of 5.6 mm is the critical value for the development of neck metastasis in oral cavity cancers. The neck metastasis risk showed a significant increase in cases where the tumor thickness exceeded this threshold value. In oral cavity cancers with a high risk of occult metastasis, the tumor thickness may be identified pre-operatively or intra-operatively and, a decision can be taken to perform neck dissection when they exceed critical values.