Preoperative measurement of tumor thickness of oral tongue carcinoma with intraoral ultrasonography.

BACKGROUND Tumor thickness of oral tongue carcinoma is an important independent prognostic factor for local recurrence, subclinical nodal metastasis, and survival. An accurate preoperative assessment of tumor thickness is therefore essential in optimizing treatment algorithm. The present study aims at evaluating the accuracy of intraoral ultrasonography in preoperative measurement of tumor thickness. METHODS Forty-five patients with oral tongue carcinoma had intraoral ultrasonography to document tumor thickness using a 7.5 MHz right angle probe. The ultrasonic tumor thickness was correlated with the fresh unpreserved surgical specimen pathologic tumor thickness. RESULTS Ultrasonic tumor thickness had significant correlation with pathologic tumor thickness. The accuracies of ultrasonic measurement of tumor thickness in staging of tumor thickness at cutoff values between 3 and 15 mm were above 91%. CONCLUSION Intraoral ultrasonography had satisfactory accuracy in the measurement of tumor thickness and is a useful adjunct in assisting pretreatment staging and prognosis evaluation of oral tongue carcinoma.