Ahab has been diagnosed with osteosarcoma, an aggressive form of bone cancer, which now explains his unusually brutal shoulder break last Spring, and his inability to heal this break despite surgery this summer and shockwave therapy last month.Osteosarcoma is by far the most common bone tumor in dogs, developing deep within the bone and becoming progressively more painful as it grows outward and the bone is destroyed from the inside out. Lameness goes from intermittent to constant over 1-3 months as the tumor grows and normal bone is replaced by tumorous bone, which results in pathologic fractures that will not heal and cannot be stabilized surgically. In 90% of cases, once the cancer is detected, generally by finding a break that won’t heal and taking a biopsy — which we experienced, it has already metastasized, usually to the lungs. Life expectancy without treatment is 2 months, often shortened because of the pain.
Yesterday we had to decide to treat Ahab or put him gently to sleep; the intense pain leaves inaction impossible. Both options are viable to us, as we would never want to prolong a painful life without hope of significant improvement, and we consider Ahab and Grendel family members, for whom we would take any step necessary to ensure good quality of life. We factored both quantity (time, based on any indication of metastasis) and quality of life (pain level, appetite, alertness, body conditions, activity level) into our decision to treat Ahab immediately — beginning with the amputation of his right forelimb. This decision was favored by both our vet and our surgeon (although neither would say that until after we had made the call).
Treatment has two objectives: fighting the extreme pain and fighting the spread of the cancer.
Fighting the Pain: Amputation of the affected limb is the only successful palliative treatment — it removes the pain immediately in 100% of cases. Ahab has moved from a stong morphine dose to 150 mg of another opiate: two Fentanyl transdermal patches — a very high dosage of narcotic that enables him to remain lucidly with us this weekend, rather than in the hospital with an IV drip. But pain-relieving drugs are relatively ineffective against this form of cancer in which, in effect, the bone slowly explodes from the inside out. Amputation alone results in a median 4 -6 month relatively pain-free life-expectancy in dogs with osteosarcoma. And amputation to a dog is relatively low-impact — dogs can compensate quickly (even great big 100 pound lab/rottweilers) and have no psychological baggage that makes it a scarier prospect for a human. They are usually up and about the same day, feeling great within 3 days, and totally healed in 2 weeks.Fighting the Spread of the Cancer: Extensive radiographs of Ahab’s lungs are clear — 7 months after the break (which the Dr. is considering the first presentation of the cancer), so he’s beating the odds right now. He is otherwise healthy and 6 years young. After the amputation, we’ll have more information to help us determine whether or not it makes sense to proceed with chemotherapy, which extends the lifespan to a median of 13 months (a lot of time in dog years), without the side effects involved in human chemo.Right now, we’ve found a way to stop the pain without losing Ahab, and to enable him to maintain a good quality of life — apparently one that’s much better than he’s known for the past few months. As for spirit, despite the enormous amount of pain, he’s already run to the gate twice today — on three legs — to bark at the cable guy. As frightening as I find surgery of any kind, and sad as we are to lose that beautiful little leg, Monday can’t come soon enough.LINKS FOR ADDITIONAL INFORMATION ON OSTEOSARCOMA:
