“Tumors in the sinus cavities are fairly common in older horses. Things to look for include nasal discharge or a small swelling between the eyes or right in front of an eye. The tumors are easier to diagnose at an equine hospital where they can take skull radiographs or scope the sinuses,” says Elce. Similar symptoms can be caused by a benign cyst or a tooth root problem in an older horse, so you need a proper diagnosis.
“If a horse has a nasal discharge, the vet may try antibiotics. If it’s a simple sinus infection, that should clear it up. The thing that should trigger a more involved workup is if you treat the horse with antibiotics for two weeks and it got better, only to recur again in a few days after the horse is off the antibiotics. This usually means there’s a tumor,” she explains.
Sinus tumors can be treated using a surgical incision through a bone flap into the sinus to remove the tumor. “They can also be treated with radiation therapy, but only a few veterinary schools can do radiation for horses. These include North Carolina State University, Ohio State University and possibly Auburn University. The cost for surgery is generally around $2,000 to $3,000 and radiation treatment is usually about $4,000 to $5,000.”