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My senior cat has sores that won't heal, losing hair. Is it cancer?

Updated On September 23rd, 2025

Pet's info: Cat | Mixed Breed | Female | spayed | 13 years and 7 months old | 20 lbs

My cat (aged around 12 and a half years) has sores that don't seem to be going away. And in some of the areas, she seems to be loosing her hair. Could this be cancer?

2 Answers

Most Helpful Answer

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Answered By Jenna Beyer, DVM, MBA, cVMA

Veterinarian, Certified Veterinary Acupuncturist

Published on August 14th, 2017

There can be many causes of sores in cats, including bacterial infection, ringworm, mites, fleas, allergies, and, yes, cancer is also a possibility. I would recommend that Carmen be examined by a veterinarian. After a thorough physical exam, your vet may recommend diagnostics like skin cytology to look at cells under a microscope, skin scrapes to look for mites, fungal cultures to identify ringworm, or biopsies to look for cancer.

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    Answered By Dr. Strydom, DVM

    Veterinarian

    Published on September 13th, 2017

    Oh my goodness! That looks really sore! Sorry that Mr. Kitty is having this issue. That looks like a reaction to a topical flea/tick medication but you did not mention using one. If you did use one, I think it may be related to that. If you did not use one, then it looks like it could be an allergic reaction to something else (like fleas) or even a burn mark (if he goes outside, sometimes get under hot vehicles and it burns them). It could be a severe bacterial infection of the skin. It could be an immune system issue like eosinophilic granuloma complex. Also, in cats, cancer is always on the list of differentials. I strongly suggest you get him to your vet for an exam. It is very hard for me to tell exactly what is going on from the photo and your description. If he has been losing weight that is also a concern so you need to let your vet know that. He needs to get some treatment as soon as possible as that looks pretty severe and painful. I hope this helps. Best wishes. I hope Mr, Kitty gets to feeling better soon.

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