Ginger is a sweet, loving, gentle girl.  She was rescued 5 years ago, so we don't know much about her.  We think she's about 11 years old and is part Labrador and maybe some German Shepherd.  (64 pounds)

She loves to go on sniffing tours around the neighborhood, be petted for hours, and have her belly rubbed by her Daddy.

She had her annual checkup in May.  No issues except an underactive thyroid which she has had for many years.

A week ago, we took her to the vet for some mild diarrhea.  He found a large lump on her rear right leg.  Took x-rays (2-3 cm mass) and a needle aspiration. A few days later, she had a biopsy, and the results came back today as bone cancer - aggressive stage II.  (I'm sorry I don't know the specific type of cancer - we were a bit too upset to really remember correctly - some type of sarcoma, so I'm assuming he must have said osteosarcoma.). (There is some bone fusion in her lower spine and mild arthritis in one hip also evident in the x-rays.)

We didn't notice the lump ourselves.  I've petted that very spot for tens of hours since May but always one side at a time - never noticing that one side was swelling and clearly different from the other. 

We have an appointment with a specialist on Wednesday.

There was clearly a very large mass on the x-ray, but it was not "surrounding" the bone or even (if I recall correctly) directly attached to the bone.  How can this be "bone" cancer when there was clear separation on the x-ray between the mass and the bone?

After the biopsy, the vet said the tumor was intertwined with the muscle - he had to separate the muscle from the tumor to get to a good location to biopsy.

Everything I've read said bone cancer is very painful, and she would have symptoms.  She had no symptoms.  She wasn't limping.  No loss of appetite or lethargy.  No weight loss.  No indication of any pain at that location (or any other location - even the bone fusion in the spine didn't prevent her from rolling around, jumping, and walking 5 miles a day when she wanted to).  She didn't want to go on long walks since the summer started, but that's normal for her.  In May we were walking 4-5 miles a day on the weekends and 2 miles a day during the week.  But, every summer she wants to stay close to home.  This summer was no different, but I took it as just her usual summer walking slump.  When we did go out every morning, she was energetic, rolling around in the wet grass, jumping up and down as we're getting ready to go out.  Just her normal happy self - still walking about a mile a day.  (And, when we walk, we go where she wants and come home when she wants - sometimes in the summer we do a mile just back and forth on the block in front of our house - so I wasn't forcing her to walk a mile in these past months when this mass has been growing.). She frequently laid on the side.

If it had not been for the mild diarrhea (which clear up in a week with medication - no parasites - seems to be unrelated), we wouldn't have had any reason to take her in - she was just there in May and was declared "perfect" (except for the thyroid).

How is it possible that she has stage II bone cancer with no indication (that we perceive) as any pain or any other symptoms?

Since the biopsy she is clearly in pain, not eating, hesitant to climb stairs or hop into/out of the car, won't lay on that side (good since we don't want the incision to be infected, but that shows she is sensitive to pain now when she wasn't before the biopsy).  She's starting to come around - back to her normal self but still not quite there.

The regular vet says he believes the leg will have to be amputated - the tumor is too involved with the muscles to save the leg.  

In humans, I've read about using chemotherapy or radiation to try to shrink the tumors before operating to help reduce the collateral damage from the surgery.  Is that an option with canine bone cancer?

What questions should I be asking the oncologist/surgical specialist when we go for our first appointment?

Julia Bell