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My dog has a large lump on his back leg. Could it be a cyst or tumor?

Updated On September 23rd, 2025

Pet's info: Dog | Bichon Frise | Male | unneutered

Hi my dog has a massive lump on his side of his back leg.near his back.it reminds me of when I had a cyst under my arm Pitt. It as exactly the same.

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4 Answers

Most Helpful Answer

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Answered By Dr. Elizabeth

Veterinarian

Published on September 9th, 2019

Pets can get many types of lumps and bumps. Most of these tumors will be benign but some will be malignant and you can't tell by looks. Here is a helpful link discussing the various types of skin masses in general: https://www.petcoach.co/article/lumps-and-bumps-on-your-pet/ Since mass is large, I do recommend to have it checked out to be safe. From to photo, it looks like there's a pink area which could represent an impending rupture. The doctor may recommend to aspirate the mass to examine the cells under a microscope. That is one of the best ways to know what it is and if further action is needed. Hopefully it's nothing serious.

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    Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on March 27th, 2017

    I can certainly understand being worried about Ri! Unfortunately in a senior dog, a lump like this could be caused by a malignant tumor. It could also be caused by a cyst or benign tumor. 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 would have Ri seen by a vet tomorrow to have this lump examined and diagnosed so it can be treated as needed.

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    Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on January 4th, 2017

    This lump could be a cyst, an abscess, a benign tumor, a lipoma (benign fatty tumor), or a malignant tumor. 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 would take your dog into the vet in the next few days to have the lump diagnosed so it can be treated.

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    Answered By David Elbeze, DVM, MRCVS

    Veterinarian

    Published on May 5th, 2018

    This lump needs to be checked and analysed as there are many conditions and types of tumors that could look like that. take Gibo to the vet, they will perform a fine needle aspiration on the growth and send it to the lab for analysis. when the result comes, the vet will advise what needs to be done according to the diagnosis.

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