Syringoid eccrine carcinoma involving the external ear canal and middle ear, first case report in Latin America

Syringoid eccrine carcinoma (SEC) is a rare, malignant, adnexal, and locally aggressive tumor. Due to their low incidence and non-specific clinical manifestation, these tumors are often misdiagnosed, even in the presence of specific histological findings. The involvement of the ear is exceptionally rare. Here we present the case of a male patient who arrived at our clinic with a non-painful nodular lesion that had developed over the course of month, located in the right external auditory canal (EAC) and post auricular area. Magnetic Resonance (MRI) and computed tomography (CT) were carried out, through which cervical lymph nodes, mastoid bone invasion, and right jugular thrombosis were identified. A type 3 lateral temporal bone resection was performed with posterior adjuvant radiotherapy and the pathology of the resected tissue was reported as a SEC compromising the EAC with infiltration to the tympanic membrane, middle ear, and parotid gland, and involvement of the sternocleidomastoid and temporal muscles, without lymphovascular invasion. At follow up, no tumor recurrence was identified. To our knowledge this is the first case of SEC with invasion of the ear reported in Latin America.