Dog must be neutered when removing masses

QI find myself in an awkward position with a 14-year-old malamute cross who weighs over 120 pounds. About three years ago, he developed some prostate issues and some growths around his anal area along with arthritis and weakness in the hind legs. My vet recommended neutering him but I thought it was probably unnecessary given his age. He has done reasonably well until recently. Now he has what appear to be six larger masses around his anal area, three of which are open and raw. His hind legs are weak.

Through family physician contacts, I was able to get ahold of some finasteride to see what it might do and checked the dosing online. After a week of medicating, I took him in to my vet, who ran blood tests that came out with normal values, and he is scheduled next week for surgery. I was told that without neutering the dog that simply removing the growths was inappropriate. Does that make sense to you?

AI wish you had reached out three years ago, at which time I would have suggested neutering your dog and removing growths that perhaps were smaller and had not yet gotten to the point where they are open and raw, as you describe, and susceptible to infection. Removing perianal masses, which can be benign adenomas or malignant adenocarcinomas, should never be done without neutering a dog since they are directly responsive to testosterone levels that come from the testicles. Simply neutering a dog can greatly reduce the size of the masses or even eliminate them.

Finasteride is used in men as a drug to treat prostatic hyperplasia and cancer, while in dogs it has been used to treat prostatic hypertrophy but must be given continuously and does not affect testosterone levels, thereby it will likely have no effect on the anal masses.

I would never advise treating your dog with drugs like that on your own without consulting with your veterinarian or a veterinary oncologist, if that’s what took place. There are risks to the dog and potentially to you, and it is practicing veterinary medicine without a license regardless of what information might be available on the internet.

Surgically speaking, there are risks such as anal incontinence depending on whether muscles and nerves in the area might be damaged. All that said, you cannot leave the dog the way he is, so you almost have to proceed with the planned surgery. I would probably only remove the open masses and neuter at this time and then reassess, hoping the other growths go down in size or disappear. Good luck.