Utility of Ultrasonography for Detecting and Diagnosing Hypopharyngeal Carcinoma

We present three cases of hypopharyngeal carcinoma detected and diagnosed by ultrasonographic examination.The cases included three men in their 50s, 70s, and 80s. Ultrasonography revealed internal nonuniform hypoechoic mass projecting into the pyriform sinus lumen. Epiglottis folds movement was maintained in the men in their 50s and 70s but not in the man in his 80s. The tumor was detected in the pyriform sinus, and a hyperechoic image that appeared to be air was observed around it.Hypopharyngeal carcinoma accounts for approximately 10% of head and neck cancers, with pyriform sinus being the primary site in 70% cases and is often diagnosed as advanced cancer with few symptoms. The three cases in this report had hypopharyngeal carcinoma in the pyriform sinus lumen.Ultrasonography revealed irregular and nonuniform hypoechoic images, indicating the possibility of hypopharyngeal cancer. Until now, observing hypopharyngeal tumors using ultrasonography was considered difficult. However, in the cases reported here, the tumors protruded into the pyriform sinus and the outline was clearly evident on the ultrasonography images due to the presence of air in the pharynx. Furthermore, the mobility of the larynx due to breathing and speech could be observed in real-time. Thus, ultrasonography may provide useful information for decisions on treatment policy and surgical procedure.In cervical ultrasonography, the pyriform sinus was mainly considered in elderly men, patients with a history of heavy alcohol consumption or smoking, and patients with cervical lymph node swelling suspected of metastasis, considering the possibility of hypopharyngeal carcinoma. It is critical to make detailed observations of the hypopharyngeal region. If ultrasonography can detect lesions before endoscopy, computed tomography, and magnetic resonance imaging, it would aid preoperative examinations in the future.