Diagnostic Pitfalls of External Auditory Canal Cholesteatoma: Insights From a Case Report

Abstract

External auditory canal cholesteatoma (EACC) is a rare occurrence characterized by the keratinized mass of squamous epithelial cells in the external ear canal, leading to bone erosion and potential damage to surrounding structures. It's often misdiagnosed as otitis externa. Both conditions exhibit similar symptoms, which frequently result in misdiagnosis by clinicians. Though it is more common in older adults, EACC can occur in younger patients, as demonstrated in the case of an 18-year-old male. Insufficient diagnosis and delays in the management of this condition can result in significant complications. While the exact cause remains unclear, contributing factors may include canal trauma, chronic inflammation, or stenosis. We aim to share the experience of this pathology in order to highlight it as a differential diagnosis. This is particularly important in patients presenting with unresolved common ear symptoms.

Keywords: canal cholesteatoma; cholesteatoma; external auditory canal; external auditory canal cholesteatoma; otitis externa.

Figure 1. Oto-endoscopic photo of right ear with keratin debris

Arrow shows part of the ear canal filled with keratin debris.

Figure 2. Oto-endoscopic photo of right ear with defect in posterior wall after ear toileting

Arrow showed bony erosion over the posterior wall of the ear canal.

Figure 3. HRCT of the left temporal bone

A, B: Axial and coronal images show a soft tissue density (white arrows) with intralesional bone fragments (*) within the left bony EAC. The middle ear cavity is preserved (angled arrow). C: Sagittal image shows focal bone erosion (arrowhead) at the posterior wall of the EAC.