Blister, boil or something else

hi all, this is my first post, i have a 41/2 year old JRTX who is in good health, the only thing is she has some kind of blister/abscess?? on her back leg it has been there for a while know and first started off looking like a small wart and then one day i noticed it it had grown to the size of a kidney bean, and then deflates again (not through bursting) it has done this a fair few times i have mentioned it to the vet he says its nothing to worry about as the dog doesn't seem bothered, which genuinely doesn't i just thought someone may have a opinion? before i take her back to the vets, thanks.

Sorry, I've never seen anything like that before.

However, if the vet says not to worry....... mind you, it may end up very sore if it gets popped....

x0x

My old collie x had something very similar, one on her leg and one on her tail. Vets said the same thing, they were cysts and to leave until they caused a problem. She had them for ages then the tail one burst so they decided to remove it to help healing and removed the leg one at the same time in case it caused further need for surgery in the future. It all healed up and never grew back. If the vet is happy to leave it, I wouldnt worry to much. Just keep a close eye on it.