Epidemiology of Congenital Cholesteatoma: Surveys of the Last 17 Years in Japan.

(1) : The incidence of congenital cholesteatoma (CC) has rarely been discussed, particularly from a demographic viewpoint. Therefore, we conducted an epidemiological study of CC using local medical characteristics. (2) : The participants were 100 patients (101 ears) who underwent initial surgical treatment at university hospitals in two rural prefectures between 2006 and 2022. A total of 68% of the patients were males and 32% were females, with a median age of 5 years. We reviewed the medical records for the date of birth, date of surgery, stage of disease, and first symptoms of the disease. (3) : The total incidence of CC was calculated to be 26.44 per 100,000 births and tended to increase. No significant difference was found between the incidences in the two prefectures. The number of surgeries performed was higher in the second half of the study period. No difference in the stage of progress was observed based on age. (4) : The incidence of CC was estimated to be 26.44 per 100,000 newborn births. The number of patients with CC tended to increase; however, this can be attributed to an increase in the detection rate rather than the incidence.