Tumor thickness as a predictive factor of lymph node metastasis and disease recurrence in T1N0 and T2N0 squamous cell carcinoma of the oral tongue.

Objective: The aim of the study was to compare the thickness of primary tumors with the frequency of nodal metastases and survival in patients surgically treated for T1/T2N0 oral tongue squamous cell carcinoma.

Study Design: This is a retrospective longitudinal study with 74 patients.

Results: None of the patients with a tumor thickness (TT) ≤ 7 mm presented with nodal metastasis, whereas 25 of the patients with a TT > 7 mm (51.0%) developed metastases (P < .0001). Multivariate analysis showed that TT > 7 mm was a risk factor for occult nodal metastasis (odds ratio = 8.7; P = .002) with 81.9% accuracy. TT > 10 mm was also a predictive factor of worse disease-free survival in these patients (hazard ratio = 12.2; P = .003).

Conclusions: Tumor thickness of greater than 7 mm is predictive of a higher incidence of lymph node metastasis, and a TT > 10 mm is predictive of worse disease-free survival in squamous cell carcinoma of the oral tongue.