Ocular Squamous Cell Carcinoma

Squamous cell carcinoma is one of the most common cancerous tumors of the equine eye.

No account yet? Register


Fear not: A variety of therapies are available to treat this common eye tumor.

Most owners are diligent about giving their horses a once-over for scrapes and swellings while grooming. This includes checking the eyes for subtle changes and early indicators of problems. Squamous cell carcinoma (SCC), for instance, is something an owner might notice; it is one of the most common cancerous tumors of the equine eye. Fortunately, with early intervention it’s treatable.

Amber Labelle, DVM, MS, Dipl. ACVO, a veterinary ophthalmologist at WestVet in Garden City, Idaho, says the most common locations for periocular (around the eye) SCC include the eyelid skin, third eyelid, and the limbus (the junction between the cornea–the clear surface of the eyeball–and the conjunctiva that covers the white of the eye).

“On the eyelid, SCC generally appears as a pink mass, often ulcerated or bloody,” she explains. “On the third eyelid or at the limbus it generally appears as a pink proliferative mass that can distort the tissues or create a mass on the surface of the eye. The tumor is generally pink or red in color.” The affected eye might squint or emit a yellow or white discharge; this is typically what the owner notices first.

Brendan Mangan, DVM, MS, Dipl. ACVO, an ophthalmologist at Affiliated Veterinary Specialists, in Gainesville, Florida, says SCC lesions and the adjacent tissue typically appear more red and inflamed than the surrounding normal tissue

Create a free account with TheHorse.com to view this content.

TheHorse.com is home to thousands of free articles about horse health care. In order to access some of our exclusive free content, you must be signed into TheHorse.com.

Start your free account today!

Already have an account?
and continue reading.


Written by:

Heather Smith Thomas ranches with her husband near Salmon, Idaho, raising cattle and a few horses. She has a B.A. in English and history from University of Puget Sound (1966). She has raised and trained horses for 50 years, and has been writing freelance articles and books nearly that long, publishing 20 books and more than 9,000 articles for horse and livestock publications. Some of her books include Understanding Equine Hoof Care, The Horse Conformation Handbook, Care and Management of Horses, Storey’s Guide to Raising Horses and Storey’s Guide to Training Horses. Besides having her own blog, www.heathersmiththomas.blogspot.com, she writes a biweekly blog at https://insidestorey.blogspot.com that comes out on Tuesdays.

Related Articles

Stay on top of the most recent Horse Health news with

FREE weekly newsletters from TheHorse.com

Sponsored Content

Weekly Poll

sponsored by:

What lameness issues has your horse experienced? Select all that apply.
268 votes · 536 answers

Readers’ Most Popular

Sign In

Don’t have an account? Register for a FREE account here.

Need to update your account?

You need to be logged in to fill out this form

Create a free account with TheHorse.com!