Hidden Peril in the Ear: A Case of External Auditory Canal Cholesteatoma in a Teenager

Abstract

External auditory canal cholesteatoma (EACC) is a rare otologic condition characterized by the accumulation of keratinized material in the external auditory canal (EAC), leading to progressive bony erosion. While typically associated with middle ear disease, isolated EACC in young patients is uncommon and often misdiagnosed. We report the case of a 17-year-old male who presented with left-sided otalgia, purulent otorrhea, and progressive hearing loss over 3 months. Otoscopic examination revealed a firm, yellowish mass occluding the left EAC. High-resolution computed tomography demonstrated a soft-tissue lesion confined to the EAC, with associated bony remodeling and erosion but no middle ear involvement. The mass was excised under local anesthesia, and histopathological examination confirmed the diagnosis of EACC. The patient experienced significant symptomatic relief postoperatively, with no recurrence during follow-up. EACC should be considered in the differential diagnosis of persistent otalgia and otorrhea, particularly when imaging reveals bony erosion of the EAC. Early recognition and surgical intervention are crucial in preventing complications and ensuring optimal patient outcomes.

INTRODUCTION

External auditory canal (EAC) cholesteatoma is a rare condition characterized by the accumulation of keratinizing squamous epithelium within the bony canal, leading to localized bony destruction occurs. High-resolution computed tomography is essential for diagnosis and for assessing disease extent. Early identification and surgical management are critical to prevent extension into adjacent structures. Clinically, patients present with otorrhea, otalgia, or conductive hearing loss, although some cases remain asymptomatic until significant osteolysis. It accounts for less than 0.5% of otologic diseases and is pathophysiologically distinct from middle ear cholesteatoma. The etiology may be spontaneous or secondary to chronic.

CASE REPORT

A 17-year-old male presented to the ENT outpatient department with complaints of left-sided otalgia for 3 months, which was severe at night. He later developed ear discharge that was scanty, purulent, continuous, and foul-smelling [Figure 1].

Figure 1.

Preoperative photo of mass in the external auditory canal

In addition, he experienced reduced hearing, aural fullness, and a foreign body sensation in the left ear for the past 3 weeks. There was no history of penetrating ear trauma, self-aural cleaning, neck pain, or facial asymmetry. The patient’s past medical history was unremarkable. Otoscopy revealed a yellowish mass completely obliterating the left external auditory canal (EAC). On probing, the mass was firm, did not bleed on touch, and allowed probe movement in all directions. An ear swab was sent for culture and sensitivity, which revealed Methicillin-Sensitive Staphylococcus aureus (MSSA), and the patient was started on appropriate antibiotics. High-resolution computed tomography (CT) of the temporal bone showed a soft-tissue lesion obliterating the lumen of the left EAC, medially limited by the intact tympanic membrane. There was no extension into the middle ear. Widening of the left EAC with remodelling and thinning of the bony walls was noted [Figure 2].

Figure 2.

Axial temporal bone computed tomography showing a soft-tissue mass occupying the lumen of the left external auditory canal, medially limited by the intact tympanic membrane

Routine blood investigations and a preanesthetic checkup were conducted in preparation for surgical intervention. The patient underwent excision of the left EAC mass under local anesthesia. Intraoperatively, a friable mass was excised entirely and sent for histopathological examination.

The EAC showed irregularities and an intact tympanic membrane. Dexamethasone-soaked gel foam was placed in the EAC, and a sterile dressing was applied postoperatively. Histopathological examination confirmed the diagnosis of EAC cholesteatoma [Figures 3-5].

Figure 3.

Excised mass from the external auditory canal

Figure 5.

Sections from the left ear external auditory canal biopsy show polypoidal nodule lined by squamous epithelium with prominent keratinous material, granulation tissue, and cholesterol clefts suggestive of cholesteatoma (H and E stain, ×100)

Figure 4.

Sections from the left ear external auditory canal biopsy show polypoidal nodule lined by squamous epithelium with prominent keratinous material, granulation tissue and cholesterol clefts suggestive of cholesteatoma (H and E stain, ×100)

DISCUSSION

Cholesteatoma is made up of stratified squamous epithelium. Its main location is the middle ear cavity along with the mastoid. Although rare, it can appear in the EAC.[1] External auditory canal cholesteatoma (EACC) is an uncommon otological condition that is defined by the pathological accumulation of keratinized material in the EAC, leading to progressive resorption of the bone.[2,3] The causes of EACC are still controversial since those are mostly postsurgical or posttraumatic in origin, with some suggestion for the primary injury being chronic inflammation, trauma, radiotherapy, or even congenital canal stenosis, but it has also been noted that ear canal stenosis or occlusion could also be causative.[2] Common clinical manifestations include otalgia, otorrhea, hearing loss, and aural fullness.[3] The frequency is one out of every thousand patients who report to new otology clinics.[2,4] Toynbee described it for the first time in 1850.[5] The variability in the clinical spectrum of EACC often leads to misdiagnosis. The primary EACC diagnosis is aided by imaging intervention because of the rarity of this condition. Other diseases of the EAC that may be included in the EACC differential diagnosis involve keratosis obturans, chronic otitis externa, necrotizing otitis externa, and postinflammatory medial canal fibrosis.[6] A retrospective study of 9 patients diagnosed with EACC found that clinical and radiological findings are essential to reduce the rate of misdiagnosis.[3]

Our case illustrated a 17-year-old young man presented with a history spanning 3 months of left-sided otalgia and subsequently developed purulent, foul-smelling otorrhea along with progressive hearing loss. Otoscopic inspection showed a yellowish mass that was obscuring the left EAC and imaging studies revealed a soft tissue lesion associated with bony erosion, which was in accordance with EACC. In this case, some clinical aspects and imaging did match those available in the literature. A review of 13 EACC cases done retrospectively reported common findings that included a soft tissue mass in the EAC with the surrounding bone erosion, and also reported the usefulness of high-resolution CT of the temporal bone.[2] Among the 48 reports available, a retrospective study noted that the most common otological symptoms, following otalgia, were otorrhea, which correlates with this case.[7] A report on two subjects aged 20 and 29, who claimed to have otalgia and otorrhea, placed particular emphasis on the role of X-ray features in the diagnosis of EACC.[8]

The primary goal of cholesteatoma surgery is the removal of the cholesteatoma and reconstruction of the EAC to prevent reoccurrence. Surgical management alternatives include endoscopic ear surgery, canal wall up, canal wall down, mastoidectomy, and canaloplasty. These alternatives are selected based on the stage and invasion level of the cholesteatoma.[9]

Owing to the reduced required time and higher visual acuity provided by the technique, endoscopic ear surgery (EES) has become more popular.[10] Patients diagnosed with EACC and subjected to endoscopic surgery demonstrated good recovery in a clinical study. Most patients reported significant hearing improvement after endoscopic surgery, especially those with a primary disease. The authors concluded that endoscopic resection is highly beneficial for stage I and II EACC, and even stage IIIA patients can obtain clinically significant results with stringent criteria.[11] For more advanced diseases in the mastoid or involving the middle ear structures, it is often preferable to perform a canal wall-up mastoidectomy with posterior canal wall reconstruction. The rationale is to remove all of the disease while preserving the ear’s structure and functionality. Dry ears were reported in most of the patients undergoing this particular procedure, and none of them developed relapses during the follow-up period from 6 months to 2 years.[12,13]

The present case illustrates the necessity of diagnosis and treatment of EACC at an early stage to avert complications, such as severe bone erosion or the development of adjacent structure involvement. Pathologic examination is still crucial for exact diagnosis, as in the confirmation of EACC in this patient.

CONCLUSION

Based on clinical history, imaging studies, surgical management, and pathologic analysis, EACC can be diagnosed. EACC can present among younger adults of both sexes, which is a significant deviation from the previously accepted assumption of only the elderly being affected. Even though it is a benign lesion, it certainly needs to be properly worked up, and the workup should include a tissue diagnosis to rule out cancer. A CT scan may demonstrate a soft-tissue attenuating mass in the EAC associated with bone erosion to the surrounding structures, occasionally containing bony fragments within the lesion. In more advanced cases, EACC may extend to the middle ear, mastoid, facial nerve canal, and the tegmen tympani. To prevent complications and for favorable patient outcomes, early diagnosis and a timely surgical approach are mandatory.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.