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Why is my dog's red belly lump growing and changing? Is it serious?

Updated On September 23rd, 2025

My dog has a red lump on his belly, which is growing. The lump used to be a flat red spot, but it’s now lumpy. Does this look dangerous, or something harmless?

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3 Answers

Most Helpful Answer

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Answered By Megan, DVM, CVA

Veterinarian

Published on April 28th, 2018

Poor Baby! Due to its dark color and it's changing nature, I would have your vet take a look at it. It could just be a benign blood cyst and nothing to worry about, but it could also be a malignant tumor that needs to be safe. If your vet isn't sure, I would have it surgically removed and sent to the lab for testing to be on the safe side. I hope this helps!

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Related Answers from Veterinarians

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    Answered By Dr. Strydom, DVM

    Veterinarian

    Published on March 5th, 2020

    Any lumps/bumps that you notice on your dog should be checked out by your vet. Lumps in this location can be any of these things: * abscess (infection) * cyst * cancer (benign or malignant) * wart There is no way I can tell you with 100% certainty what it is just based on your description or by looking at a photo but my best guess is that it is probably a histiocytoma. ( https://veterinarypartner.vin.com/default.aspx?pid=19239&id=4952066 )

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    Answered By Dr. Strydom, DVM

    Veterinarian

    Published on November 27th, 2017

    That is most likely a histiocytoma: https://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=1676 It could also be a cyst or a plugged hair follicle. It is hard to say just by looking at the photo. My recommendation would be to take her to your vet to have it checked. If it is a histiocytoma it may go away on it's own within a few weeks to months. Hope this helps.

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