DOI: https://doi.org/10.36347/sasjs.2026.v12i07.010

Pages: 631-636

Introduction: Primary malignant tumors of the external auditory canal (EAC) are rare. Among them, adenoid cystic carcinoma (ACC) arising from the ceruminous glands is an exceptional entity, whose clinical and radiological presentation may mimic a benign lesion, thereby delaying diagnosis. Case report: We report the case of a 63-year-old woman who presented with an EAC mass evolving over 4 months, associated with otalgia. Otologic examination revealed a round, smooth, sessile mass of the outer third of the EAC, obstructing visualization of the tympanic membrane, which appeared normal on the visible portion. Preoperative computed tomography (CT) suggested an EAC lipoma based on a fat-density lesion. Surgical resection of the mass was performed. Histopathological examination showed a tumor proliferation with cribriform and tubular architecture, lined by monomorphic cells developing within a hyaline cylindromatous stroma. Immunohistochemical analysis concluded to an adenoid cystic carcinoma of the ceruminous glands. The patient was referred to the National Institute of Oncology for further management. Postoperative MRI showed no evidence of residual or recurrent tumor, a finding confirmed on a second MRI performed 7 months later. Discussion: This case illustrates the diagnostic difficulty posed by ceruminous gland ACC, whose radiological appearance can be misleading, as well as the essential contribution of histopathological and immunohistochemical examination to a definitive diagnosis. Management, mainly surgical, and prolonged clinical and radiological follow-up are discussed in light of the literature. Conclusion: Any EAC mass, even one with a radiologically benign appearance, warrants histological vigilance. Ceruminous gland ACC, although rare, must be considered and requires long-term follow-up given its potential for late recurrence.