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My dog has a large, fluid-filled lump on her leg. What is it?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed Large (61lb +) | Female | unspayed | 4 years and 9 months old | 65 lbs

Hi my dog has had this lump on her front right leg for about a month now and out of no were it got very big it is not solid it feels like fluids are inside but also doesn’t seem to bother her but I no it does I need answers so bad

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1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on April 9th, 2019

Oh that's quite large! This could be a cyst, benign 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 its cells, and examines the cells on a slide under a microscope. It's usually painless to the animal, and relatively quick to perform. Once the cause of the lump is diagnosed, the vet can discuss treatment options if needed. Give Mj's vet a call to make her an appointment. Best of luck.

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