During the past few years, the oncology team at Washington State University (WSU) has successfully treated several horses with cancer using radiation therapy. Previously, this type of treatment was considered an unrealistic option for horses with cancer.

But WSU’s advantage is its linear accelerator. One of the most advanced machines in the world dedicated to animal cancer treatment, the linear accelerator in WSU’s Veterinary Teaching Hospital uses either electron beams or high-energy X ray radiation to treat tumors with minimal impact to the surrounding healthy tissue. This tool delivers focused radiation therapy exactly like that used with human cancer patients, while being large enough to accommodate a horse.

WSU oncologist Janean Fidel, DVM, MS, Dipl. ACVR, ACVIM, believes radiation therapy is a highly viable option for treating numerous equine tumors, including common skin tumors such as melanomas, sarcoids, and squamous cell carcinomas.

"Even though cancer is not as common in horses as dogs or cats, it does still occur and, just like in small animals, radiation therapy is a valuable tool in the treatment of our equine oncology patients," said Fidel, who works with WSU’s equine team to treat horses that come to the Veterinary Teaching Hospital in Pullman