In Reference to Utility of Esophagrams to Detect Prevertebral Invasion in Hypopharyngeal carcinomas

Abstract

We would like to appreciate the efforts of Kaffenberger et al. in describing the utility of an esophagogram in assessing prevertebral fascia invasion in an advanced stage hypopharyngeal carcinoma. We have few doubts regarding this retrospective study and would like to clarify with the author about the initial intent of a preoperative esophagogram for better understanding. Was it to assess degree of aspiration and laryngeal dysfunction or is it routinely used to assess prevertebral fascial involvement at their institution? The author measured the excursion of the hyolaryngeal complex relative to the patient’s vertebral bodies, but it could be affected by tracheostomy and radiation fibrosis. Decreased laryngeal elevation due to the presence of a tracheostomy tube, especially with the cuff inflated has been reported in several studies. Ding and Jung et al. suggested that the findings from their study may support the hypothesis that a tracheostomy tube may disturb hyoid bone and laryngeal movement during swallowing. Conversely, Terk et al. reported that the tracheostomy tube did not significantly change hyoid bone and laryngeal movement. It may be that a tracheostomy tube impacts the biomechanics of swallowing in individuals with dysphagia or perhaps hyolaryngeal excursion may be diminished. Thus, is there a possibility of false positivity with esophagogram in this subset of patients? If details related to trachesotomy and results of esophagogram could be furnished it would enable the readers to assess the applicability of this diagnostic modality better. Most of the patients with the advanced-stage disease might have a tracheostomy. As the author described, Radiation-induced fibrosis can cause reduced elevation of the larynx in patients treated with radiation therapy alone or chemoradiation. Along with this finding, they can have dysphagia due to weakness of posterior motion of the base of the tongue, lack of coordination of swallow phases, reduced laryngeal closure, reduced epiglottic inversion, and prolonged pharyngeal transit time. If we consider both esophagogram and MRI images are almost predicting the prevertebral invasion equally, MRI will have a dual benefit of assessing the disease extension with prevertebral invasion and esophagogram may not be needed as a separate investigation to look for the invasion. Meerwein et al. suggested that advanced imaging technologies like PET CT /MRI predicts the prevertebral invasion with an accuracy rate of 98%. Even though with high accuracy, future prospective studies should compare with the gold standard surgical assessment with the recent images.