Retrospective evaluation of ceruminous gland tumors confined to the external ear canal of dogs and cats treated with biopsy and CO2 laser ablation

Abstract

Background: Treatments currently available for ceruminous gland tumors include surgery and radiation therapy, which come with high financial costs and frequent complication and recurrence rates.

Hypothesis: To evaluate the treatment, response, complication, and recurrence of ceruminous gland tumors confirmed with biopsy and ablated using CO₂ laser.

Methods: Retrospective review of medical records from Iowa State University and the University of Illinois between January 1, 2016 and December 31, 2021. Electronic medical records were evaluated for a histopathologically confirmed ceruminous gland tumor via video-otoscopic aided biopsy and subsequent CO₂ laser ablation. Signalment, tumor type, size, location within the ear canal, length of time tumor was present before presentation, advanced imaging, and follow-up including recurrence were assessed.

Results: Fourteen ceruminous gland adenomas (4 dogs, 10 cats) and 12 ceruminous gland adenocarcinomas (7 dogs, 5 cats) were identified. Bacterial otitis externa was present in 4/26 (15%) animals. Recurrence was identified in 1/14 (7%) ceruminous gland adenomas and 1/12 (8%) ceruminous gland adenocarcinomas.

Conclusions and clinical importance: Video-otoscopic aided biopsy and CO₂ laser ablation of ceruminous gland tumors in dogs and cats is a viable treatment option with low recurrence and complication rates with CO₂ laser ablation.

Keywords: CO2 laser; ceruminous adenocarcinoma; ceruminous adenoma; ear tumor.