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What causes a lump or bump on my cat's back and what should I do?

Updated On September 23rd, 2025

Pet's info: Cat | American Shorthair | Male | 6 lbs

My cat has a lump or bump on his back

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1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on June 16th, 2018

If Yellow Cat is allowed outside, this lump could be an abscess. Cats who go outdoors can get into fights with other cats, and bites from other cats frequently lead to abscesses. These are very painful to the cat, and need to be sterilely drained and flushed, and oral antibiotics prescribed to treat the infection. Other causes of the lump include a cyst, a benign tumor, or a malignant tumor. I would have him seen by a vet first thing in the morning to have this lump examined and diagnosed so it can be treated as needed. Best of luck.

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20Pet Parents found this answer helpful

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