Malignant external otitis following radiotherapy for oral cancer: A case report

RATIONALE: Although an ototoxicity is well-known as adverse event of the radiotherapy, it is not widely known that immunosuppressed patients who underwent radiotherapy in head and neck region have risk of malignant external otitis. PATIENT CONCERNS: A 68-year-old man with diabetes, who had been diagnosed as intraosseous squamous cell carcinoma of the right mandible, underwent surgical resection. He received a total of 60 Gy/30Fr postoperative radiation. Four months after the course of radiation, he suffered from right aural fullness, otalgia and otorrhea. DIAGNOSES: Clinical examination revealed granulation and existence of Pseudomonas aeruginosa in the external auditory canal. Computed tomography showed expansive inflammation and erosion in the temporal bone. The patient is elderly and diabetes. These findings led to the diagnosis of malignant external otitis. INTERVENTIONS: The ear irrigation and administration of quinolones were started. Afterwards, fistula was formed in the oral cavity, and connected to the right external auditory canal. Therefore, irrigations were performed not only from ear but also from the oral fistula. OUTCOMES: Eight weeks after starting treatment, the malignant external otitis was completely healed. LESSONS: Physicians should raise awareness of malignant external otitis in immunosuppressed patients with oral cancer after radiotherapy.