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My dog has a red lump on his leg. Is it a mast cell or benign tumor?

Updated On September 23rd, 2025

Pet's info: Dog | Golden Retriever | Male | neutered | 7 years old | 85 lbs

7 y o English cream golden has a tumor on hind leg. Found after being shaved for summer. Looks like histiocytoma pea size red elevated. No loss of appetite. How to make sure no mast cell. Vet busy for a month.

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1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on May 15th, 2018

This bump on Simba could be a histiocytoma, but it could also be a wart or another type of benign tumor. A mast cell tumor is another possibility, but the only way to know for sure is to have the vet perform a fine needle aspirate on it. You can call your vet and ask to be put on a cancellation list, meaning they call if you they have a cancellation and you can take that appointment. If you are very worried about it, see if you can get him in with another vet in your town sooner. Best of luck.

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