Canine Cancer....... Im sorry Hilts... I had a Boxer once that developed throat cancer... lost her when I was 6, best friend I ever had. Tore me up for weeks... Cancer isn't fun, whether it be in Dogs, people.... God forbid even cats. My family has been rocked by cancer, never a fun word to even say. 
Here is to healthy futures, all around 
Well, the saddest thing is the fact that had we caught it earlier, and done a couple of things different, Gretchen would have done much better. We found it when she suddenly collapsed in early 09. It seems that the associate at the vet's office thought there might have been a problem in mid 08. But he didn't really tell us anything. When she collapsed, then he told us. By then, Gretchen was very sick. We opted for surgery because Gretchen was so strong, and so full of life, she acted like a 2 year old even with the tumor when she was recovering from a bleed.. My regular vet thought she'd never survive the surgery. But she was up and around in 30 minutes, despite having her spleen removed, along with a tumor that filled a 2 gallon bucket. Gretchen only weighed 85 pounds. She had lost enough blood to need two transfusions, that caused problems with clots. She survived those, too. I think she picked up a nasty virus on her last visit to the vet to pay off the bill and show how well she was doing. She died the next day.
Had we found the tumor in mid 08, she would never have been so weakened, she wouldn't have lost much blood, and the cancer would not have seeded. I don't think the virus would have gotten her, she wouldn't have been weakened by the clot, and she probably wouldn't have had to deal with the cancer coming back had she lived a while. Had she had a the spleenectomy in mid 08, she'd probably still be with us. She was otherwise extremely healthy, with no real joint problems, no heart, digestive, or respiratory problems, nor any other problems they could find. My regular vet was heartbroken when she died, he felt she'd made it over the hurdles, and would live at least 6 months, longer depending on if the seeded cancer grew or not. The people in his office dearly loved that dog, she was "the best dog I ever worked with", no matter who you asked.
It's amazing how much Bear acts like Gretchen, except for his temperament being somewhat weaker. I think his previous family was pretty rough on him, and being a pup from a BYB, I'm certain he is not of excellent stock, although he is a good solid dog. I'm sure he went "home" too soon, and that makes for temperament issues. He's getting better, but I'm not sure he'll ever be a really strong tempered dog.