Utility of sonography for evaluation of clinical T1 and T2 glottic carcinoma.

OBJECTIVE

The aim of this study was to evaluate the prognostic impact of sonographically determined tumor features in relation to local control of clinical T1 and T2 glottic carcinoma treated by definitive radiation therapy.

METHODS

Between 1999 and 2005, 72 patients with T1 and T2 glottic carcinoma were evaluated by percutaneous sonography in terms of tumor detectability, maximum tumor dimension, involvement of the anterior commissure, presence of supraglottic, subglottic, or paraglottic spread, and thyroid cartilage invasion. Factor analyses for local control included clinical features, sonographic findings, and treatment factors.

RESULTS

Forty-one lesions (57%) were detected as hypoechoic masses on sonography. For detectable T2 tumors, sonographic and laryngoscopic findings were in agreement in all cases with respect to spread to anatomic subsites. The 3-year local control rate with radiation therapy alone was 82%. Univariate analysis of the sonographic characteristics revealed that the maximum tumor dimension and thyroid cartilage invasion predicted a loss of local control, whereas none of the clinical or treatment characteristics was significant. Multivariate analysis showed that thyroid cartilage invasion was an independent negative prognostic factor for local control.

CONCLUSIONS

Sonography provides information about the likely outcome of radiation therapy for patients with clinical T2 glottic carcinoma, although its utility for T1 lesions is not proven. Thyroid cartilage invasion may be an independent negative predictor of the outcome.