My labrador is a 10 month old and he developed a lump on his back the size of a baseball. took him to the vet and he made a cut in his back about 6" long to drain the fluids, after 2 weeks the lump is back and he reopen the wound, there was no major fluid inside but the muscle is enlarged, has anybody experienced anyhting like this? I hate to see my baby going to this again and the vet doesn't really know what is causing this, the lump is very hard but doesn't seem to hurt my dog is very playfull still and is eating well, but the wound looks terrible any coments or help will be very apprecciated thank you.