I hate cancer. Almost everyone I know has been touched by that horrible disease in some way, whether personally, through one of their family members, or one of their pets. As I start a new year of columns on Animal Health, I can think of no more scary or depressing topic, but cancer touches so many of our pets’ lives that it is important that we understand how to prevent, recognize, treat, and live with, cancer in our pets.
Before I start, let me share why I hate cancer so much. I lost my dad to esophageal cancer 25 years ago when he was only in his early sixties. A longtime smoker, Dad had kicked the habit even before the Surgeon General’s famous report on the links between smoking and cancer, but developed esophageal adenocarcinoma because of chronic gastric reflux disease. I’ve inherited that problem from him, but daily “Prilosec” has changed and saved my life…if only we had that option years ago. (Note to all: if you have chronic heartburn, don’t just reply on “Tums.” Get checked out and treated properly…it really does make a difference.)
We have lost other family members to liver cancer, breast cancer, and colon cancer, and have had dear friends battle pancreatic cancer, brain tumors, and leukemia. I hate cancer because it hurts those that we love. It is a debilitating disease which is physically painful and often requires unpleasant and invasive treatments.
Cancer is also on my “#@!! List” because of the fear and unease it causes. Whether a patient, a family member, or an owner of a pet with cancer, it seems that for so many a black cloud hangs over them when a diagnosis of cancer is made. Much of that unease is well-founded, but some of it comes from misunderstanding what cancer is, how it affects us, and the options available to treat it. That is why I dare to start off the new year with such a depressing topic: so we can see some light at the end of the tunnel.
First, let’s look at cancer itself. Not one disease, cancer is actually the common name given to many diseases in which the normal cells of the body begin to multiply in an inappropriate and uncontrolled manner. Within the broad categories of cancer there are even more sub-groups – there are many types of breast cancer, for instance – and each type may have dramatically different causes, treatments, and expected outcomes.
While we’re at it, let’s review a few specific terms and definitions:
TUMOR is the term used to describe any lump, bump, or discrete mass. Tumors may be BENIGN, meaning that they don’t spread to other areas and are generally less dangerous, or they may be MALIGNANT, meaning that they can METASTASIZE (spread to other parts of the body.) Generally, a malignant tumor is called a CANCER. LEUKEMIA refers to abnormal cells in the bloodstream. NEOPLASIA is another technical term for cancer, meaning “new-growth”, an abnormal accumulation of cells.
Some cancers have specific causes, but many don’t. Some types of cancers are more common in certain breeds of dogs or in cats with certain lifestyles. The routine recommendations for care that your veterinarian shares with you takes many of these facts into account, and he or she is the best source of information on what you can do to minimize and mitigate the risks of cancer in your pet.
Cancers cause such devastating effects either by interfering with the normal organ function, taking nutrition away form normal tissues, or directly damaging the tissues in which they are found. Lung cancers, as an example, may cause breathing problems by growing and blocking airways, causing fluid to fill the lungs, or allowing severe secondary infections. Liver tumors may obstruct the flow of bile in the liver (causing jaundice) and prevent the liver cells from performing their important normal biochemical functions. Leukemias replace normal blood cells with abnormal ones so that the blood may not carry oxygen properly or fight-off infection well.
Cancer is diagnosed in several ways. Some cancers form discrete tumor masses which can be felt or seen on X-Rays or other scans. Other cancers, such as leukemia, can be detected through certain blood tests. In pets, most cancers are first discovered by the family. On many occasions a lump or bump is found while the pet is being petted or groomed. Sometimes a cancer is found when the family notices that their pet is breathing hard, coughing, or losing weight. That is why it is always important to have a close relationship with your pet so that you can tell when something is different. We can only help diagnose cancer in a pet when its family has brought it to our office, whether for a routine exam or because they suspect a problem, and the earlier you discover something at home the sooner we can get to the bottom of the problem.
Whenever a cancer problem is suspected, the only certain way to diagnose it is by biopsy and lab testing. Some biopsy techniques are as simple as using a needle and syringe to draw a small sample of cells from a suspected tumor and sending it on a slide to a laboratory. Some biopsy exams are done after samples have been taken at surgery. Specialists may perform biopsies during an ultrasound or other imaging procedure. Pathologists can examine the biopsy specimens to detect the presence and type of cancer cells, and can define the “name and address” of the tumor.
This examination is very important, not only to know if a cancer is present, but to determine the specific type of cancer so that proper treatments can be planned.
Treatment for cancer in pets has advanced just as it has in humans, and therapies such as surgery chemotherapy, radiation, and even immunotherapy (using the body’s immune system to fight the tumor) can be used to help the pet and the family affected by cancer. Each type of cancer is different, and each family and pet with cancer has different needs.
That, for me, is the most difficult and the most important apart of the whole subject of subject of cancer, and is the area where we can be of the most help. There is not a “one size fits all” approach to cancer; you and your vet should discuss in detail all of your options. For some pets and some types of cancer there are straightforward steps which can essentially provide a practical cure, and I generally can offer an excellent outcome. For other situations, aggressive and intensive therapies may be needed to either fully diagnose or treat the cancer problem, with an uncertain opportunity of success. And, unfortunately, some cancer problems do not respond well to any therapy, and care is best focused on providing comfort and freedom from pain. Our discussions with pet cancer families should always honestly communicate both the facts and the feelings involved with the disease.
Let me briefly share the story of several of my recent patients’ journeys with cancer, and perhaps you’ll get some insights on how some families are living with this frustrating chronic disease.
Just today I diagnosed bone cancer in “Jackson”, owned by one of my oldest and dearest family friends. Jacksonis a senior lab- a great dog who means much to them. He has had arthritis for some time, and we have successfully treated him for several years with anti-inflammatory medicines. His owner recently noticed a change in the way he walked, limping more specifically on his left front leg. When I was at their home I could detect specific pain in his upper “arm”, and I asked them to come in today for X-Rays. Unfortunately, the radiographs confirmed my suspicions that a tumor was growing in the upper humerus in his left foreleg, and we found an additional growth in his pelvis. The particular type of tumor that we suspect is resistant to effective treatment, and although we are discussing all options, we are likely to provide comfort care forJackson, preventing pain with medicine and assisting his mobility. In several months, I am afraid the problem will have progressed, and we are likely to need to help him in another, more final, way. Jackson’s family knows that they have loved and cared for him well over the years, and although sad, don’t want him to experience pain or indignity.
Also today, I operated on “Misty”(not her real name), a senior Pomeranian with mammary tumors (breast cancer). Because she was indoors and away from other dogs, her family had never had her spayed. (Unspayed female dogs who continue to have hormone cycles are at increased risk for breast cancer.) Her mom noted some lumps on her lower abdomen, and our examination showed that multiple small tumors were present. Because mammary tumors often spread rapidly, we referred her to a cancer specialist inCharlotteto have body scans looking for any metestatic growths. Fortunately, none were found. I performed a partial mastectomy on her today, and spayed her to remove the hormone influence that could have encouraged further growth and spread of the tumors. After biopsy results are back we may make additional recommendations, but many of these patients do very well once the tumors and hormones are removed.
The story of Beau (another name-change) perhaps best illustrates the perspectives on cancer that I hope you remember from this article. Beau developed a small bump on his nose over a year ago which initially looked like an infection. After it did not respond to therapy, we tested it, and eventually removed the bump. Final testing revealed a “Mast Cell Tumor,” one of the most common skin cancers we see. Because of its location, it was impossible to remove a wide area of normal skin around it, so Beau’s family chose to have follow-up chemotherapy with an oncology specialist. Beau responded very well to the therapy, with minimal side-effects, and just today I received a Christmas Card with a picture of Beau happily playing in the snow. He is considered cured, although none of us can ever predict the future with certainty.
Regardless of the type and progression of a cancer problem, you can KNOW that you are helping your pet in the right ways by fully discussing all of the options for treatment with your veterinarian. Cancer is a terrible disease (as you may remember, I hate it), but it is a part of life and can in many cases be managed. Learning to live with challenges is a reality we all must face on our journey through life, and I’m glad that our pets can help us enjoy both the journey and the challenges.