Evaluating oropharyngeal carcinoma with transcervical ultrasound, CT, and MRI.

OBJECTIVE: To compare transcervical ultrasonography (US) to standard cross-sectional imaging for the visualization of human papillomavirus-related oropharyngeal cancer (HPV-OPC). MATERIALS AND METHODS: Patients with HPV-OPC and available standard imaging (CT and/or MRI) were identified in clinic and prospectively enrolled. US was performed to visualize the oropharynx and lymph nodes. Tumor characteristics across imaging modalities were evaluated (CT versus MRI, and US versus standard imaging (SI)). RESULTS: Forty-three patients were included. The overall blinded detection rates for CT and MRI were 83% and 71%, respectively. The unblinded detection rate for US was 98%. Agreement of tumor anatomic subsite was moderate for both CT vs MRI (κ = 0.59) and US vs SI (κ = 0.47). Comparison of tumor size by CT and MRI showed statistically significant correlations in craniocaudal (CC), anteroposterior (AP), and mediolateral (ML) dimensions (RhoCC = 0.51, pCC = 0.038; RhoAP = 0.81, pAP < 0.0001; RhoML = 0.57, pML = 0.012). Tumor size estimates by US and SI showed statistically significant correlations in CC and AP, but not ML (RhoCC = 0.60, pCC = 0.003; RhoAP = 0.71, pAP < 0.0001; RhoML = 0.30, pML = 0.08). Tumor volume estimates improved correlations between US and SI (Rho = 0.66, p < 0.0001). Stratification of US patients into early and late imaging studies demonstrated an increase in correlation strength from early (Rho = 0.32, p = 0.32) to late groups (Rho = 0.77, p < 0.0001) demonstrating that ultrasound accuracy improved with experience. CONCLUSIONS: Our findings suggest that transcervical ultrasonography is a sensitive and relatively accurate adjunct to standard imaging for the evaluation of oropharyngeal tumors. Its cost, portability, and potential for in-clinic and serial imaging render US an attractive modality to further develop for imaging oropharyngeal tumors.

Reader performance in the ultrasonographic evaluation of oropharyngeal carcinoma.

OBJECTIVE: To examine reader performance in evaluating oropharyngeal anatomy on ultrasonography. MATERIALS AND METHODS: Ultrasound images of the oropharynx comprising normal and malignant anatomic variants were organized into slideshows. Slideshows were administered to 6 readers blinded to participant tumor status and with varying experience reading oropharyngeal sonograms. A training slideshow oriented readers to images of the oropharynx with and without malignant lesions. Readers then evaluated images in a test slideshow for tumor presence and marked orthogonal long and short dimensions of the tumor. Results were analyzed for accuracy, sensitivity, specificity, inter-reader agreement, and measurement error relative to prospectively-identified reference measurements. RESULTS: Eighty-seven percent of base of tongue (BOT) sonograms were identified correctly by a majority of readers. In identifying BOT tumors, median accuracy, sensitivity, specificity, and Fleiss's kappa were 79%, 73%, 85%, and 0.51, respectively. Median measurement error in the long and short axes for BOT tumors was -2.6% (range: -40% to 29%) and -2.6% (range: -56% to 156%), respectively. Eighty-four percent of palatine tonsil sonograms were identified correctly by a majority of readers. In identifying tonsil tumors, median accuracy, sensitivity, specificity, and Fleiss's kappa were 77%, 74%, 78%, and 0.41, respectively. Median measurement error in the long and short axes for tonsil tumors was 3.8% (range: -45% to 32%) and -6.5% (range: -83% to 42%), respectively. CONCLUSIONS: Overall, US has clinically useful sensitivity for identification of oropharyngeal carcinoma among readers of diverse clinical backgrounds and experience. US may be useful for the evaluation of features such as tumor dimensions.