my dog has a bump

i have a mini pin and there is a bump that looks like a boyle that comes up on his back it has busted a couple of times and this stinky stuff that looks like can dog food came out of it. it never went away it just keeps coming  back and its gettng larger what could this bump be and how can i get rid of it without it coming back?

[ginger899]

I would take your dog to the vet and get this thoroughly treated. It sounds very much like a recurring abscess. If so, it will be quite painful for your dog. And if it keeps recurring, AND doesn't get any smaller each time....then that is beginning to get serious. You do not want this infection (if it is that) to spread through your dog's system. Maybe an antibiotic treatment will be recommended if it's an abscess.
Go to the vet. I would go either today or tomorrow.