Chemo-Thermo Treatment

What is chemo-thermo treatment?

The UF Large Animal Hospital Medicine service is now offering chemo-thermo treatment for horses. Intralesional chemotherapy is administered in conjunction with focused hyperthermia to treat horses with skin cancers such as melanomas, sarcoids and squamous cell carcinomas. The combination of chemotherapy and hyperthermia has proven to be beneficial to horses with large inoperable melanomas that interfere with bodily functions and performance.

What is hyperthermia therapy?

Hyperthermia therapy is delivered painlessly by a portable microwave device that uses less power than a standard light bulb. It fights cancer cells by heating tumors up to 113 °F; thereby, boosting natural body defenses and enhancing the effects of other treatments such as radiation and chemotherapy. Hyperthermia appears to be particularly effective for treating tumors such as melanomas in gray horses that are resistant to chemotherapy alone. This type of treatment is also thought to relieve pain and promote tissue healing. The hyperthermia applicator can be used safely even around sensitive areas such as the eyes and ears.

How many chemo-thermo sessions does my horse need?

The number of sessions is determined on a case-by-case basis, but one to three sessions are usually sufficient. The first visit will begin with an initial evaluation by one of our veterinarians to determine whether your horse will benefit from this type of treatment. If your horse is a candidate, he or she will receive one round of intralesional chemotherapy followed by two rounds of hyperthermia.

Please keep in mind that this is a two and a half day process. Your horse will need to return to the UF Large Animal Hospital in two weeks for re-evaluation and to determine whether additional treatment is needed.

Patient success story

B’s Silver Pumba, a 19-year-old driving pony, had a history of melanomas and was admitted to the UF Large Animal Hospital for an examination of large masses on the right side of the throatlatch. The masses were interfering with the bridle, which was causing performance issues while being driven.

An ultrasound was performed and a biopsy was taken from the masses for further evaluation. Unfortunately, due to the critical location of the masses, surgery was not recommended because of the high risk of complications. Owner, Roberta Hager, was given an alternative option: chemo-thermo treatment.

After two chemo-thermo treatments, the masses had shrunk impressively in size and B’s Silver Pumba was able to return to competition.

B’s Silver Pumba and owner, Roberta Hager, competing in a combined driving class at Black Prong Equestrian Center
Photo by Pics of You

More Information

The UF Large Animal Hospital veterinarians treat equine and large animal patients from the Gainesville, Ocala and Jacksonville areas, including Alachua and Marion Counties in Florida, and our clients come from all over the United States. Contact us to speak to one of our specialists or to make an appointment.

Dr. Rob MacKay

Information provided by Dr. Robert MacKay, Veterinarian of the UF Large Animal Medicine service, Professor at the UF College of Veterinary Medicine, and Diplomate of the American College of Veterinary Internal Medicine.

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