Is Ultrasound a Useful Adjunct in the Management of Oral Squamous Cell Carcinoma?

PURPOSE: In patients with oral squamous cell carcinoma (OSCC), depth of tumor invasion (DOI) is correlated with prognosis. Tumor thickness (TT) is often used as a surrogate measurement of DOI. The aim of this study was to estimate TT in a sample of patients with OSCC using ultrasound sonography (USS), magnetic resonance imaging (MRI), and clinical assessment and compare these estimates with TT of the final surgical specimen.

MATERIALS AND METHODS: The authors designed and implemented a prospective cohort study and enrolled patients presenting for management of OSCC. Eligible subjects had biopsy-proved OSCC and received clinical assessment, staging by MRI, and USS. The predictor variable was measurement technique by clinical assessment, USS, or MRI. The primary outcome variable was the maximal TT (centimeters) obtained from the final histopathologic specimen. Appropriate uni- and bivariate statistics were computed.

RESULTS: The sample included 10 patients (mean age, 62.7 ± 13.6 yr; 70% men). Two of the 10 tumors (20%) were not adequately visualized with USS. Three of the 10 tumors (30%) were not seen with MRI because of dental artifact. These 3 patients' tumors were visualized by USS. One of the 10 tumors (10%) could not be palpated clinically. Three of the 10 patients (30%) did not go to surgery and were treated with chemoradiation because of the high tumor stage or the patient's health status. USS, MRI, and clinical TT measurements were underestimates compared with the specimen TT measurement (-0.6, -0.5, and -0.3 cm, respectively; P = .9).

CONCLUSIONS: All 3 measurement modalities (clinical examination, MRI, and USS) underestimated OSCC TT compared with the final surgical specimen. There were no statistical differences in mean measurement or absolute value mean differences among measurement modalities. Notably, USS visualized the OSCC in the 3 patients (30%) whose tumors were poorly visualized or not visualized with MRI.