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My dog has a strange lump, is lethargic, and won't eat. What is it?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed Small (up to 22lb) | Male | neutered | 18 lbs

I found this on my dog and I don't know what it is. He is acting very lethargic and hasn't eating very much today. What is that?

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1 Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on April 18th, 2018

That appears to be a lump on Dusty, and it could be benign or malignant. There is a possibility that if this lump is malignant, that it could be causing him to be lethargic and not eat much. The lethargy and anorexia could be completely unrelated to the lump. Any suspicious lumps should be examined by the vet. The vet can perform a test called a fine needle aspirate on it. To do this, the vet sticks a small needle into the lump to get a sample of it's cells, and examines the cells on a slide under a microscope. It's usually painless to the animal, and relatively quick to perform. I recommend calling your vet to have an appointment made for him in the next couple of days to have this lump checked out, as well as his anorexia and lethargy. Best of luck, I hope this helps!

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