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What is this ballooning lump on my cat's leg? Should I worry?

Updated on September 23rd, 2025

Pet's info: Cat | Domestic Mediumhair | Male | neutered | 9 lbs

Just found this “ballooning” on my cats leg

1 Answer

Most Helpful Answer

Answered By Rodrigo Roca, DVM

Veterinarian

Published on January 1st, 2019

Hello, thank you for your question about Milo.

Based on the photo that you have attached it is possible that this lesion could be due to a cyst, abscess, or mass. A cyst is a benign fluid filled structure that can develop in various locations on animal's bodies. An abscess is an encapsulated infection that is most commonly associated with some kind of trauma, but can occur for an unknown reason. Masses, tend to feel more firm/solid and can be caused by many different types of cancers (benign or malignant).

I would recommend having Milo evaluated by your veterinarian so that they can examine the lesion. They may recommend collecting an aspirate, or small needle, sample from the lesion to help determine exactly what it is. They can then discuss further treatment options based on these findings.

Hope this helps, good luck!

1Pet Parents found this answer helpful

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