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My dog has a small lump on her back. Is it a cyst or cancer?

Updated On September 23rd, 2025

Pet's info: Dog | Pit Bull Terrier | Female | spayed | 2 years and 9 months old | 75 lbs

My pitbull has a small what seems to be a cyst on her back, It has not shrunk or grown. Its also under her fur coming out of her skin. She likes to rub her back on the wooden deck and concrete patio in the sun so I figured it could be from that, I just want a second opinion on if it could be a tumor/cancerous before I bring her to the vet. Thank you!

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5 Answers

Most Helpful Answer

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Answered By Linda G, MS, DVM

Veterinarian

Published on September 4th, 2020

Hello. I really do not think this is cancerous or a tumor. It does look like a small cyst, or even a benign skin tag, so just keep an eye on this for now, but do not worry, just show this to your veterinarian at Evie's next scheduled visit. Thanks for contacting Petco Pet Education Center, formerly Petcoach.

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    Answered By Emily, DVM

    Veterinarian

    Published on June 11th, 2017

    This looks like it could be a cyst or even a zit like mass. Rarely skin cancers can form. If this lump does not go away or gets bigger your veterinarian needs to do an exam. Do not apply any medications or ointments to it.

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    Answered By Cara, DVM, cVMA

    Veterinarian

    Published on August 19th, 2017

    I would have your vet examine Lexi as a mass cannot be identified just by looking at it. They will get a sample using a needle and have it analyzed to determine if it is benign or malignant. It may need surgical removal, but if it's fluid filled it may be a cyst which are typically benign.

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    Answered By Andrea M. Brodie, DVM

    Veterinarian

    Published on January 10th, 2019

    This may be an abscess, a cyst or a tumor. You should have it examined by your veterinarian, as it is not possible to distinguish these by just looking at a photo. An abscess can usually be treated with antibiotics and/or be lanced, and a cyst can be evacuated. To identify a tumor, your vet may want to do a fine needle aspirate (he takes some material from the bump with a needle and then looks at it under the microscope) to determine whether the mass is concerning.

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    Answered By Karly Macon, DVM, MS, CVA Certified Veterinary Acupuncturist

    Veterinarian

    Published on April 4th, 2017

    Hi there. Emmy could have any number of things going on. This sound like a small tumor that your veterinarian can identify by drawing cells from the mass with a needle and looking at them under a microscope. This is called cytology from a fine needle aspirate. This is not an emergency, but at your convenience you should schedule an appointment with your vet.

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