We have all heard the word cancer and the innate negative connotations that are associated with it, and rightfully so. The word for many hits far too close to home. You may have a two legged or four legged family member or friend that has battled the disease. It may even be you who has gone through or is currently battling cancer.
My job as a veterinarian is not only to alleviate pain and suffering in animals, but to educate pet owners in our community about the health care of their four legged family members.
First things first: When talking about cancer, we have all heard the familiar terms associated with the disease: cancer cells, mass, growth, lump, tumor, malignant, benign, metastatic, etc. But, these terms are often misused or misunderstood by pet-owners which can cause confusion. So, before we go on, listed below are some basic terms and their definitions. Understanding the differences between these relationships should help when discussing the topic of cancer with your veterinarian.
Cancer: Uncontrolled abnormal changes or mutations in the cells of our body that have the tendency to spread and affect the way other parts our body work.
Cells: Microscopic units that collectively make up the tissues in our body. i.e. skin cells, muscle cells, blood cells. The normal healthy cells of our body is unfortunately where the cancer process begins.
Mass—Tumor—Growth—Lump: You will often see these terms used interchangeably. These are nearly synonyms of each other when referring to abnormal changes in the skin or an organ. These are not synonymous with cancer, but can be determined to be cancer with proper diagnostics testing.
Metastasis: Refers to the spread of abnormal cancerous cells from one site in the body to other sites or organs. i.e. The cancer metastasized to the lungs OR spread to the lungs.
Malignant: Malignant tumors can invade and destroy nearby tissue and spread to other parts of the body. Cancerous cells are synonymous with malignant cells.
Benign: Tumors that are not a danger to health nor have the tendency to spread or be malignant. Benign tumors are not cancerous.
The normal cycle of our body’s cells are as classic as the life cycle principle in general. Cells are born, they get old, they die and new ones are made so we continue to live healthy lives. There are many factors that alter this beautiful cycle when considering how cancer actually happens and why. The truth is, we don’t know exactly why it happens but genetic factors are thought to play a significant role, as well as environmental factors including sun exposure, exposure to chemicals, smoke, pesticides, viruses, and in rare cases, certain vaccines in cats have been known to cause cancer.
Every part of the body that contains cells can be affected by cancer. Skin, eyes, bone, brain, heart, lungs, liver, kidney, pancreas, intestinal, urogenital, even our blood and lymphatic system. That is nearly everything but hair and nails!
There are many types, subtypes, and groups of cancer. Considering the massive amount of detail that is available, I will suffice it to say, it is often acceptable when referencing cancer to begin with the organ or area that is affected and generalize. For example, bladder cancer or colon cancer. For those interested I will list the main groups or classifications of cancer.
Carcinoma – cancer that begins in the skin or in tissues that line or cover internal organs. There are a number of subtypes of carcinoma, including adenocarcinoma,basal cell carcinoma,squamous cell carcinoma, and transitional cell carcinoma.
Sarcoma – cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.
Leukemia – cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood.
Lymphoma and myeloma – cancers that begin in the cells of the immune system.
Central nervous system cancers – cancers that begin in the tissues of the brain and spinal cord.
Some of the more common cancers seen in dogs are lymphoma, mast cell tumors of the skin, mammary cancer often related to unspayed females and bone cancer, seen especially in large breed dogs.
We see cancer less often in cats than dogs, but when it happens it tends to be fairly aggressive. The more common cancers seen in cats are lymphoma, often associated with contracting the leukemia virus, oral cancers, and in some cases as mentioned earlier, cancer associated with vaccine injections. The benefits of receiving the protection of vaccines, far outweigh the risk of getting a vaccine associated cancer in cats.
Please refer to your veterinarian regarding types, frequency and risks of vaccination in cats.
So how does one know if their pet potentially has cancer? I will start by recommending your pets make the annual or bi-annual visit to your veterinarian’s office for routine physical exam and vaccines. A thorough physical exam from head to toe can be the determining factor in finding early signs of cancer. Your veterinarian should feel the entire surface of your pets body, look into the eyes, ears, mouth, listen with a stethoscope to the heart and lungs and recommend diagnostic testing when appropriate either due to abnormal physical exam findings or for patients that are in their senior years.
In addition to routine check ups, be mindful of any changes in your pets daily routine AND pet your pet often! By petting and caressing your pet, it not only has proven benefits to you and your pets health and general well being but you may also be able to detect early changes such as a skin growth or an enlarged belly which may indicate an enlarged organ or tumor. If your pet has changes in appetite, water drinking, activity, urination or defecation habits, shows signs of pain, vomiting or diarrhea, these may all be precursors to cancer or just as importantly, precursors to other major disease processes that may need to be addressed. And remember, spaying and neutering reduces the incidence of mammary, prostate, and testicular cancer.
So what if your dog or cat is diagnosed with cancer? Once the diagnosis is made, your veterinarian will discuss options depending on the type and severity of the cancer. These may include surgery, chemotherapy, radiation therapy or other medical therapies. And remember, your veterinarian should be able to help in determining which of these treatments are best for everyones particular situation, that includes considering the entire family. Sometimes it can be difficult to make a decision when considering all the options both prognostically and financially, so I encourage as much communication as possible between you and your veterinarian. I encourage asking questions, no matter how big or small. No question is a stupid question when trying to understand and make the best decision for your beloved companion.
Now I’d like to introduce you to Bradley Colacion, an 11 year old French Bulldog with a fighting heart and soul and his mom, Kathy who is amongst the most committed of pet owners. Bradley came to me with a lengthy medical record. Just prior to the diagnosis of bladder cancer in late 2011, Kathy noticed Bradley straining to urinate and his urine appeared to have some blood in it. That is what prompted her to make the first visit to her veterinarian. After a series of tests from her veterinarian and referrals to Oncologists(Cancer specialists), Bradley was diagnosed with the most common cancer that can affect the bladder, a Transitional Cell Carcinoma. The cancer had severely invaded his bladder and urethra making it difficult to urinate and he was initially given months to live. Mrs. Colacion took every recommendation from her veterinarian and the specialists and currently has Bradley on a course of medications that helps control his symptoms enough that Bradley has a great quality of life with his family for a longer period of time. He has already beaten the odds. Bladder cancer will eventually take it’s toll on Mr. Bradley Colacion, but until that day, Mrs. Colacion and her family are dedicated to monitoring his quality of life and assuring he is happy and pain free.
Cancer is an unfortunate process that has cut so many lives short. If we cannot fully prevent cancer in our loved ones, we can at least exhaust our efforts to decrease the chance of it happening.
The more we know about the health care of our beloved pets, the better lives they live and the happier we all live together.
Key points to aid in early detection of cancer:
1. Spay and Neuter your animals
2. Keep current on vaccine recommendations and yearly physical exams
3. Be aware of changes in your pets normal daily routine.
4. Pet your pets often!
5. Communicate with your veterinarian often, remember no question is a stupid question when it comes to the health and well being of your beloved companions.
If you have any questions regarding the information in this article or would like more specific information on a particular type of cancer in pets, please do not hesitate to call or stop by our office or visit your own veterinarian
Pet Cancer Awareness
ISSUU – Las Vegas Pet Scene Magazine, May-June 2013 by Homes Illustrated/LV Pet Scene by Dr. Leslie Stewart