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My senior cat has a growing blackish-blue lump on his leg. What is it?

Updated On September 23rd, 2025

Pet's info: Cat | Mixed Breed | Male | neutered | 15 lbs

My cat is about 15-17 years old. I've noticed a small blackish blue lump on his leg and over the past month I've noticed a difference in size. No hair is on this lump, he has been an indoor cat since we have gotten him. What can this be?

1 Answer

Most Helpful Answer

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Answered By Destini R. Holloway, DVM

Veterinarian

Published on June 26th, 2017

His lump is likely a mass. I would recommend getting samples taken from this mass and having your vet send them off for analysis to see if this is something to be concerned about (cancerous) or not. Most masses cannot be identified just by looking at them, which requires analysis of the cells that make up the mass. I hope that everything works out for Kitty and hopefully this is a benign mass that isn't something you need to be concerned about. Best wishes and take care.

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