My Dog Has a Lump

If you are worried, see another vet. I would.

Hope it is just fat and that it doesn't bother the dog.

If it does bother the dog, you might want to insist on having it removed.

You can usually tell if it's just a fatty lump because it can be
easily moved about and you can get your fingers around it. It's tethered but usually at one point unlike other growths that feel far more solid and fixed. Also the vet should do a fine needle aspiration, they pierce the lump with a needle and draw out fluid which when placed under the microscope can be seen as fatty fluid.

One of the little dogs upstairs has a fatty lump on one of her hips. She's very old. She had one removed a couple of years ago but it's grown back. The vet said it was an old age thing and no danger to her. It doesn't seem to bother her.

Our dog has quite a few lumps. Vet confirmed they are just fatty and require no treatment.
On the other hand, our last dog died age 12. He had one pretty large lump.
Vet checked and said it was ok. A few months passed and lump was growing. Dog had a seizure one night.
We had to call another vet as our own wasnt answering.
New vet investigated lump with blood tests. It was cancer and dog was given weeks to live.
We found out our original vet hadnt had blood test done. Really neglectful and this vet we discovered has a poor reputation in area.
So you no doubt know to keep checking lumps for growth. Hope your pet will be ok.

Is your dog elderly alexa? Older dogs oftan develope fatty lumps. They can become quite large. Keep an eye on the surrounding skin if it becomes red or darker in colour or sensitive to the touch get the vet to look again also if dog begins to scratch at it. Mostly these lumps are fat and nothing to worry about. Your vet will be happy to check regularly if it puts your mind at rest.

My daughters lab had a fatty lump, it did gradually grow and when it became annoying both to lab and daughter it was removed. Very straightforward.