how can you tell if your dog has prostate cancer?

my 12 year old dog suddenly has a lump near his butt...is that a sign of prostate cancer or is it just the anal sacs needing to be expressed?

Only a vet can tell you that.

Take you guy to the VETs. It could be something simple or it could be bad. The longer you wait the more miserable you baby will be.

take your dog to the vet please. the vet is the only one that can tell you what is wrong.

Well it depends on what kind of lump the dog has on it's butt. If it is near the anus, then it is probably his glads being inflamed because they need to be expressed. Usually if it is the glads that are the problem, your dog will start smelling horrible. He would be rubbing his butt on the ground and it would be really irritated. Butt if it is different and it really seems to be an issue, make sure to call your vet and make sure that it isn't. i hope I helped!