by Dr. Doug Pernikoff, DVM
Clarkson-Wilson Veterinary Clinic & Vet Pet Rescue
Growths arise on our pets at all ages and at all stages of life. By strict definition, a tumor is any kind of growth. That being said, a pimple can be called a tumor, but it is NOT a cancer or a malignant growth. Those latter terms are pretty synonymous and refer to growths that are potentially life threatening, and are able to move to other body sites, impacting numerous organs in many cases. The end result is typically NOT a good one.
Veterinary medicine is becoming more and more sophisticated in regards to technology and therapeutic options for many conditions in pet care. Most tumors, which again are benign or harmless growths, can be managed with surgical removal of the masses. This response is typically enough! Some tumors like lipomas, or fatty tumors, can re-occur at any time. Therefore, it is not uncommon for many veterinarians to suggest NOT removing lipomas unless they are in areas that would impede movement. There are other tumors like histiocytomas, that arise most commonly in young dogs, and are either surgically removed, or in many cases, will resolve and disappear without further intervention.
Cancers and malignancies can be anywhere in the body. The treatment options include surgery, radiation therapy and/or chemotherapy, involving many of the same drugs used in human cancer therapy. The decision regarding which approach of treatment, or which combination of therapies, are most appropriate, depends on the tumor type and the scientific research supporting the best approach.
There are several tumors that are frequently treated in animals. Others are less likely to be managed.
Mast cell tumors are usually found on the skin, in one or more locations. They tend to be masses of an oblong shape and not very big. I find most of them to present with hair loss on their surface. Mast cell tumors are generally removed surgically, being careful to take wide margins, as tumors may migrate out from the primary growth, and not be grossly visible. Only the histopathologist can accurately ‘stage’ and ‘grade’ the tumors. The prior term regards to the presence of tumor in other body sites(metastases); and, the latter term regards the percentage of cells that are dividing, called the ‘mitotic index’, thereby providing a prognostic evaluation for the particular mass in question.
Lymphomas or lymphosarcomas are another malignant tumor type that is often treated with reasonable success, meaning that treated pets can go into remission for up to 1 or more years often.
Again, the protocols suggested by your veterinarian will either come directly from the current literature, or possibly, through supervision of a specialized veterinary oncologist. This particular tumor is often presented with swellings under the throat and to the side of the neck. These are lymph nodes that are primary sites where the tumor cells reside.
One final cancer group to mention include post-vaccinal ‘shot’ sarcomas, most commonly seen in cats. That is why many vets are inclined to place immunization injections in the lower leg regions in the event that these persistent and dangerous cancers return, forcing one to consider limb amputation in order to stop the progress of these cancers.
The University of Missouri has recently established a Cancer Diagnostic and Treatment Center in Wentzville, Missouri, a great plus for our pet community. Additionally, there are not less than three specialty clinics in the St. Louis region, hosting specialists in veterinary oncology, and other aspects of veterinary internal medicine. In the event that you see specific tumors appear in your pet, or if your pet is older and showing signs of general decline, you are best to plan a visit to the vet to assess the best path to take. Good luck and enjoy the beautiful springtime.
Fondly, Dr. Doug Pernikoff: 636-530-1808.