Killing Cancer: How Veterinarians Are Keeping Dogs Hunting Longer
June 17, 2015
Four of the most gut-wrenching words a veterinarian can utter are "your dog has cancer." It's a life-changing diagnosis that strikes all-too often (the Animal Cancer Foundation says one in four dogs will develop cancer). Among retrievers, rates of lymphomas and mast-cell tumors are fairly high, and goldens are particularly susceptible to angiosarcomas.
However, there is good news to report: Thanks to a series of medical breakthroughs, canine cancer is no longer a death sentence.
"Just like with human patients, we're getting far better at helping animals with cancer live a whole lot longer and a whole lot better," says Dr. Gerald Post, veterinary oncologist at The Veterinary Cancer Center in Norwalk, Connecticut. "There are several reasons for this: We're now able to detect cancer earlier, resulting in more effective treatments; the therapies themselves are getting more effective; and there are a lot more interventions to mitigate the side effects of therapy."
Arguably the greatest advancement in cancer treatment is veterinarians' ability to target the disease — even its specific sub-types — while sparing healthy cells. Radiation treatments, for example, are vastly improved thanks to the development of CT scans and "intensity modulated radiation therapy." Radiation more accurately kills cancerous cells while avoiding surrounding tissues, improving effectiveness and decreasing side effects.
The modern era has also seen development of "targeted therapy" drugs, which attack a specific molecule found only in certain cancer cells. Thus, the tumor is reduced and/or prevented from spreading with minimal side effects.
"They're really revolutionizing cancer treatment," says Post. "We can now target the specific defect resulting in the cancer growth."
Currently, two such drugs are approved in the U.S.: Palladia, which targets mast-cell skin tumors; and Kinavet, prescribed for recurrent or non-operable mast-cell tumors.
Chemotherapy, too, is increasingly tailored to individual cases.
"We're getting better at chemotherapy protocols that are more specific to the sub-type of cancer the dog has," Post explains. "Veterinarians also increase or decrease dosage based on how the pet is handling it and how the disease is responding."
Reduced Side Effects
If the cancer is caught early and chances of survival are high, in this era it's often worth the fight.
"The very word 'chemo' evokes thoughts of 'I'd never do that to my pet'," says Post. "But oncologists have gotten so much better at utilizing chemo drugs. Not long ago, it was normal for 10 to 20 percent of dogs being treated for cancer to end up in hospitals due to side effects. Today it's less than one percent."
Anti-nausea, anti-diarrheal and other meds can now be prescribed proactively rather than in response to side effects.
When considering the type of treatment, you must also contemplate the cancer's level of advancement.
"It's incredibly important for cancer to be caught early," Post advises. "Early detection does more than anything else to extend the life of your retriever."
According to Post, here are the top 10 symptoms to watch for: swollen lymph nodes; an enlarging or changing lump; abdominal distension; chronic weight loss; chronic vomiting or diarrhea; unexplained bleeding; a dry, non-productive cough; lameness; straining to urinate; and oral odor.
Note that these ailments can have a variety of causes that aren't necessarily cancer-related. Still, they warrant a veterinary examination.
Post says the best way to prevent cancer is by ensuring your dog eats a balanced diet and gets plenty of exercise — I assume your duck dog already has that covered. Sound like the same advice given to humans? There's a reason for that.
"Dogs are affected by the same cancers as people," says Post. "They get spontaneous cancer, like people, and their cancers behave similar biologically. In fact, knowledge gained fighting cancer in dogs could one day help people, too."