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My dog has a lump on her back knee and is sick. What should I do now?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed Small (up to 22lb) | Female | 20 lbs

My dog trixi has a lump on her back knee. Shes had it for a while. I haven't noticed it bothering her but I do want to know what it is so if you could help that would be great. She has also been getting sick often for the past few days.

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1 Answer

Most Helpful Answer

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Answered By Ricardo Fernandez, DVM

Veterinarian, Veterinary Oncology Resident

Published on January 30th, 2018

Thanks for using Petco Pet Education Center, formerly Petcoach! This could be a benign or malignant growth. This is often differentiated by a test called a fine needle aspirate (FNA) which is a pain free, inexpensive and easy procedure which in most cases will help reach a diagnosis. Sometimes a biopsy is needed for a definitive diagnosis. I recommend that you have her evaluated by your veterinarian for further assessment and treatment. They can also see why she has not been feeling well. I am really hoping for something benign. Good luck and have a good day!

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