While a cancer diagnosis in your dog can be devastating, treatments are becoming more effective, methods of diagnosis are allowing earlier detection, and new vaccines and immunotherapy treatments are bringing hope for many cancers in dogs. Let’s look at a few.
Osteosarcoma is a primary bone cancer, most common in large or giant breed dogs who are over four years old. It usually begins as a tumor in one of the limbs, and is highly metastatic, meaning it travels to other organ systems such as the lungs or lymph nodes. Dog owners may notice a limp or favoring a leg or paw, but many times the cancer has spread before any symptoms are noted.
Aratana Therapeutics has received conditional approval from the USDA for their canine vaccine against osteosarcoma. It is an immune-based vaccine, and uses the dog’s own immune system to fight the cancer. Initial clinical studies show that dogs who have been diagnosed with osteosarcoma and receive the vaccine in addition to other treatments have a delay in metastasis, or the vaccine prevents metastasis all together; in addition, the vaccine prolongs survival in treated dogs. The only noted side effects are lethargy, fever, and diarrhea.
As part of the conditional approval, Aratana is conducting extended field studies of the vaccine. The vaccine has been made available to around two dozen veterinary oncology practices across the country. Dogs who are diagnosed with osteosarcoma and enroll in the extended clinical field studies can receive the vaccine.
Lymphoma is a cancer of the blood, and is very common and highly treatable. Early symptoms can include swollen lymph nodes under the jaw or behind the knee. As the disease progresses, dogs may have weight loss and lethargy. Some dogs develop swelling in the face or legs. Most of the time, lymphoma itself doesn’t cause pain. There are a number of therapies with good track records, and clinical trials are proceeding to test new immune therapies and treatments for resistant or malignant lymphoma. If looking for a clinical trial near you, check the listings of the Pet Cancer Center for clinical trials that are enrolling participants.
Hemangiosarcoma is a cancer of the blood vessels, and it appears in dogs more commonly than any other species. Diagnosed in middle aged or older dogs, it seems to be more common in German Shepherds, Golden Retrievers, and Labrador Retrievers. There are two types. When the disease is limited to skin lesions, it can usually be cured with surgery alone. Unfortunately, nearly 50% of cases involve the spleen or heart. Many times this very aggressive form of cancer has become malignant and spread before any symptoms are noticed.
Dogs with hemangiosarcoma get ill very quickly, and if they have the splenic type, the prognosis is poor. There are treatments, however. The standards of practice include an extensive surgery to remove all tumor that can be located, followed by chemotherapy. The surgery is often complicated by the disease itself, which has an impact on the blood and the dog’s ability to stop bleeding and form clots. The standard chemotherapy is with doxorubicin, a chemo agent that has been used for years; it is usually given every three weeks. Other chemotherapeutics such as vincristine and methotrexate have had less effectiveness against this highly malignant form of cancer. Radiation therapy is usually not recommended.
Since this cancer is so highly localized to dogs, and within dogs to large breeds, some researchers suspect this is a heritable condition, and comes down in certain bloodlines.
Two university-based studies may offer some hope for this devastating cancer. In 2012, the University of Pennsylvania did a research study with clinical trial of the Yunzhi mushroom. The active compound, polysaccharopeptide, was isolated in a supplement called I’m Yunity. The small study yielded surprising results, with prolonged survival in the dogs treated.
A more promising study is currently underway at the University of Minnesota. Their novel therapeutic agent eBAT is showing considerable efficacy in clinical trials; a phase three trial in their Shine On Study has been enrolling participants to look for an early detection test. Since this cancer so often doesn’t show specific signs until treatment is futile, an early detection test will change the face of what has been a cancer with a very poor prognosis. Researchers are looking at potential uses for humans.
Mammary tumors are most common in female dogs who are older and who are intact. The risk over the lifetime of a dog who has not been spayed to develop a mammary tumor is a whopping 25%. About half of these are benign and half malignant forms of cancer. They are commonly seen as a lump or thickening in the areas over the mammary gland; while the overwhelming majority of cases are female dogs, they can occur in male dogs as well.
Treatment is usually surgical removal of the tumor. If the tumor appears to have metastasized, the surgeon may also remove lymph nodes. Chemotherapy is seldom used. If the female is still intact, they will usually be spayed at the time of the surgery to improve prognosis. The overall prognosis depends on if the tumor is found to be benign or metastatic; these tumors in male dogs tend to have a more serious prognosis.
Glioblastoma is a particularly deadly form of brain cancer than affects both dogs and humans. There have been few treatment options, but new studies at the University of Minnesota, underwritten by the National Institutes of Health, are studying several promising treatments. The researchers used some of the dog’s own tumor cells to develop individual vaccines; these tumor lysate vaccines, while effective, tended to wear off over time, with the cancer recurring.
Researchers are also developing gene-based immunotherapy, and adenovirus based gene therapy. While the adenovirus therapy also tended to wear off over time, leading to a recurrence, the therapy did prolong life and had no side effects. Researchers are hoping to move ahead from these preliminary findings with a new added peptide which they hope will deal with the issue of the efficacy decreasing over time. They have developed both vaccines and gene-based immunotherapy treatments for the current trials. Researchers are watching the trials carefully, with the hope that the results can bring about new treatments in human glioblastoma as well.
Can we answer your questions about cancer in dogs? Please get in contact for more information or an appointment.
Annie, my Golden Retriever Mix, is not a patient there, but got both her Flu vaccines at Tipp City Vet.
The First one, was at their drive up clinic and the second one at their office.
Both were fantastic experiences! The staff (Dr Jim Mathias, the Vet Techs, and Front office) were all super friendly, professional, and great with Annie! And they were very accommodating too, as I had to change my appointment a few times, in order to fit my ever changing schedule.
If I didn’t already have a vet that I love, and am very loyal to; I would definitely make the 30 minute drive to their office!
Always happy with the staff. Lots of space so the pets can have their own space. The most honest Dr.s ever. These people truly care, they aren’t just trying to make money off of you. They want what’s best for your pet.
Nice and knowledgeable staff. They were extremely patient with our crazy cat and didn't try to just strong-arm her like other offices did.