I have a 20 year old gray Egyptian Arab. He has 6 melanomas; 2 in his mouth, 4 in his sheath. My personal vet said that he would need surgery only if they grew. My question is that even if they do not grow what would be the cheapest way to treat them and what would be the most effective way to prevent more without paying a fortune? Thanks for any help at all. CB, North Carolina

Dear CB,

Managing melanomas in horses can be controversial. Although these skin tumors are generally considered benign in gray horses such as yours, that doesn’t mean they don’t lead to problems. It just means they don’t aggressively invade local tissue or spread throughout the body (metastasize). But melanomas inside the mouth and sheath could obstruct normal bodily functions or get irritated and chronically ooze. And because most of them DO eventually grow larger, many veterinarians will advise you to treat them now–while they’re small and causing no harm—rather than wait until they’re large and complicated. Treating them sooner rather than later will also be less expensive.

The fact that I’m going to share several treatment options is both good news and bad news. It’s good news because you and your veterinarian have several medical and surgical choices to select from in a wide variety of price ranges and aftercare needs. It’s bad news because this means no one method reliably works better than another. It’s not uncommon for a melanoma to be removed only to come back, and more than once. And unfortunately, I can find no information on preventing new ones from popping up.

I recommend you ask your veterinarian about the following options: traditional surgery, laser removal, radiation, cisplatin injections and oral cimetidine (an anti-ulcer medication). Keep in mind that combining options might give you the best outcome. Consider getting a second opinion from another veterinarian if your personal veterinarian is firm on the subject or not up-to-date on the latest treatments.