Necrotizing Otitis Concealing Carcinomas of the External Auditory Canal.

External auditory canal Carcinomas are rare and aggressive tumors and their prognosis depends on early diagnosis. Their clinical similarity to necrotizing otitis is a source of error and therefore of diagnostic delay. Hence the interest of our study which consists in providing ENT specialists and all practitioners with the necessary clinical, evolutionary, radiological, biological and histological elements to avoid diagnostic errors. This is a retrospective study of all patients who were hospitalized for necrotizing otitis in the department of otolaryngology of the hospital of specialties of Rabat spread over a period of 5 years. All patients received an admission CT scan, biological tests, bacteriological sampling and biopsy. As well as initial parenteral antibiotic therapy and surgery for incidentally discovered EAC carcinomas. Clinically, all patients had otalgia and granulation tissue on otoscopic examination under the microscope. 50% had otorrhea. Pseudomonas aeruginosa was isolated in 50% of the cases, staphylococcus aureus in 25% and sterile culture in 25%. From the first biopsy, the diagnosis of tumor was retained in 6/10 patients. A second biopsy was performed in patients who did not show improvement and had a sterile culture. This one allowed the diagnosis in 4 other patients. All our patients had a surgical indication and were operated and then irradiated. The survival at 5 years was 50%. Biopsy must be systematic for every patient hospitalize for necrotizing otitis. Without hesitating to do it again each time the evolution is not good and the culture is sterile.