2018 Volume 22 Issue 2 Pages 161-166
Cranial nerve palsy is a rare complication in patients with nasopharyngeal carcinoma (NPC) who have received radiation therapy. In this study, we report a case of dysphagia due to lower cranial nerve palsies as a late complication after 14 years of radiation therapy for NPC. A 38-year-old man with aspiration pneumonia was admitted to the department of respiratory medicine; he had received radiation therapy and chemotherapy for NPC at 21 years of age. He had episodes of difficulty in swallowing at 35 years of age and dysarthria at 36 years of age. Since then, he had experienced frequent paroxysm of fever. On admission, physical examination revealed right hemiatrophy of the tongue (right hypoglossal nerve palsy) and mild hypesthesia of the right pharyngeal wall (right glossopharyngeal nerve palsy). Furthermore, disturbance of salivary secretion was found, and total molar teeth loss due to dental caries and periodontitis was recognized. Antibiotic therapy for pneumonia and oral exercises were initiated. Videofluoroscopic examination of swallowing showed pharyngeal residue, and most foods were passed through the left side of the pharynx. After remission of pneumonia, the patient was transferred to the department of otolaryngology for further evaluation and treatment. In addition, videoendoscopic examination of swallowing revealed laryngeal penetration and right vocal cord paresis (right glossopharyngeal and vagus nerve palsies). Direct swallowing training was initiated, and postural adjustment with rotation of the head was conducted. In addition, a nutrition support team intervention was initiated, and easily chewable and swallowable foods (Code 3 of Japanese Dysphagia Diet 2013 by the JSDR dysphagia diet committee) were provided. After receiving swallowing therapy, the patient eventually achieved full oral intake. Lower cranial nerve palsies (right hypoglossal, glossopharyngeal and vagus nerve palsies), as a late complication of radiation therapy, is considered as the main cause of dysphagia. Disturbance of salivary secretion and the related total molar teeth loss may be also involved in dysphagia. The understanding of the dysphagia mechanisms with videofluoroscopic and videoendoscopic examination, swallowing therapy including postural adjustment, and nutrition support team intervention may contribute to the achievement of oral intake. Although the patient could fortunately achieve oral intake, long-term follow-up of the patient is required, because the course of late complications of radiation therapy is usually slowly progressive and refractory. Recently, the combination of chemotherapy and radiation therapy is persistently performed to improve prognosis of NPC. Note that the incidence of dysphagia due to late development of cranial nerve palsies may increase in the near future in exchange for improvement of prognosis.
