Pediatric Congenital External Auditory Canal Cholesteatoma Extending Beyond the External Auditory Canal: A Case Report.

This article describes an extremely rare case of pediatric congenital external auditory canal cholesteatoma (EACC) that extended beyond the external auditory canal. A five-year-old girl presented with progressive swelling in the posterior wall of the left external auditory canal. Computed tomography of the temporal bone revealed a well-defined round mass that compressed and eroded the posterior canal wall without invasion of the mastoid tegmen, sigmoid sinus, or tympanic membrane. Surgical exploration via a retroauricular approach confirmed the presence of a cholesteatoma extending from the external auditory canal to the mastoid cavity; furthermore, complete excision was achieved. There has been a recent increase in the number of reported EACC pediatric cases, especially in East Asia. However, few studies have clearly distinguished congenital and acquired forms, which could be largely attributed to challenges in differential diagnosis, particularly when lesions extend beyond the canal. Based on our findings, we propose radiological and clinical features that may facilitate differentiation between congenital and acquired EACC, even in advanced-stage cases. This article highlights the importance of accurate classification for elucidation of the pathogenesis of EACC and optimization of surgical decision-making in pediatric patients with EACC.