Could this lump be cancer?

[ginger899]

I have found a lump on my dog's breast. It was there a couple of months ago, and I took her to the vet who said it was a lymph node up a bit. But I didn't think so. However I did as instructed, and kept an eye on it. It didn't go away, and has grown a little bit bigger. I am going to take her back either tomorrow or Saturday. But am posting here in case you can give me any advice in the meantime. The lump is perfectly spherical, firm, feels unattached to anything inside the breast. I can actually 'lift it up' under the skin and wobble it about. It gives her no pain. It is about 1/2 inch in diameter. Of course I am taking her again to have this looked at, but does this sound like it could be a cancerous lump to you? I certainly don't think it's a lymph node, but who am I to know..? Thanks for any advice you can give.

[Dan Sims, DVM]

If a dog is spayed before the first heat cycle the odds of getting mammary cancer
is zero.
Lymph nodes are found in the groin typically usually not in the mammary gland itself.
A simple test called a fine needle aspirate will yield the answer and then you will know if surgery is needed.
Every time a female dog goes through a heat cycle the chances os mammary cancer gets greater so get the fine needle aspirate done ASAP.

[Aleda M Cheng, D.V.M., C.V.A]

I am very happy to hear the good news!

[ginger899]

Thank you.
I'll post an update on this. I took her to the vet today and he was about 100% certain this was a harmless cyst. He examined her very thoroughly. And told me to watch this cyst and make sure it didn't get too much bigger, but as it was very 'mobile' and not attached in any way to undelying tissue, and had a very defined rounded shape (encapsulated) he said it was a perfect example of something benign. If of course it changed in any way, any time in the future, I should bring her back in, and they would either do a fine needle aspirate or more likely, he said, take the whole cyst off. But he told me it doesn't need surgery right now as it's quite harmless. However he did agree that it is ALWAYS the best thing to take any lump whatsoever to be checked out by the vet.
We celebrated with a gravy bone.

So my already lumpy-as-a-rice-pudding dog has another lump to add to her collection!