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My 9-year-old dog has a marble-sized leg lump. What should I do?

Updated On September 23rd, 2025

Pet's info: Dog | American Cocker Spaniel | Female | spayed | 9 years and 8 months old | 21 lbs

My dog has a lump on her leg roughly the size of a marble. She is a 9 year old cocker spaniel and is very healthy otherwise.

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3 Answers

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on February 4th, 2018

Thank you for providing a picture of Mia's lump! It could be a benign tumor, a cyst, or a malignant tumor. Unfortunately in a senior dog, there is always a chance it could be malignant. 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 her into the vet in the next couple of days to have this lump examined and diagnosed so it can be treated as needed. Good luck, I hope this helps!

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    Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on June 27th, 2017

    Thank you for providing a picture of Kelly's lump! In a senior dog, there's always a chance it could be a malignant tumor, but it could also be a benign tumor or a cyst. 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 Kelly into the vet tomorrow or the next day 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 June 25th, 2017

    Unfortunately in a senior dog like Libby, there is always a chance this lump could be a malignant tumor. It could also be a benign tumor, but the only way to know for sure is to have her seen by a vet. 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 Libby into the vet tomorrow to have this lump examined and diagnosed so it can be treated as needed.

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