Squamous cell carcinoma of an eyelid in a horse: A case report
The aim of this report is to describe a clinical case of squamous cell carcinoma in an 18-year-old horse. This tumor is one of the most common superficial oncological problems in these animals. A lesion in the lateral corner of the eye was already observed about 10 years earlier, but due to the lack of significant growth or alarming symptoms, no diagnostics or treatment was implemented. A year before surgery, an episode of acute inflammation in the eye and a slight enlargement of the nodule occurred. Initially, an autoimmune origin of the lesion was assumed, but anti-inflammatory and bactericidal treatment did not lead to a significant improvement. As a result of sampling for histopathological examination, the tumor doubled its volume, so, given the inefficacy of the subsequent anti-inflammatory and antibiotic therapy, the horse was sent to the clinic. A convex, painful lesion partially covering the cornea was found on arrival. In view of the rapid growth of the tumor and its infiltration of surrounding tissues, a decision was made to carry out transpalpebral enucleation. The procedure was performed under general anesthesia and with an additional retrobulbar block. Because of significant tissue tensions and the risk of hematoma, an intermittent horizontal mattress suture was used. The area was secured with a compression dressing. The horse returned to sport, and no recurrence of the tumor was observed up to 7 months after surgery. Histopathological examination confirmed squamous cell metaplasia forming keratin pearls, characteristic of squamous cell carcinoma.