Be on lookout for cancer in aging pets

Did you know that cancer accounts for almost half of the deaths of pets over age 10? Of course, we see cancer in younger pets, too, so it is something we have to always be on the lookout for. In fact, cancer in dogs is as common as cancer in people. Cats are a bit luckier in that there are fewer cancers that affect this species, but we still need to be watchful for it.

Cancer is essentially the growth of abnormal cells that the body, for some reason, is unable to control. As with people, cancer in pets can be benign, meaning that it is less harmful and won't spread to other parts of the body. Or cancer can be malignant, meaning that it will grow and invade other tissue. Some cancers stay in one place and grow locally, eventually forming a huge mass in one place, while others spread throughout the body by way of the bloodstream or lymph vessels.

Sometimes a veterinarian knows to look for cancer because of a symptom that a pet is displaying. Other times, we actually can feel or see the cancer as a lump or bump. However, we often have to perform special testing, such as X-rays, blood tests or ultrasounds, to find evidence of cancer. Once cancer is suspected from the tests, a biopsy (removal of a piece of tissue for a pathologist to examine microscopically) is necessary to confirm the presence of cancer.

Often the pathologist can give us an idea of the severity of the cancer and whether it is benign or malignant.

The cause of most cancers is not known, so they can be very hard to prevent. We know we can reduce the risk of ovarian, uterine, breast and testicular cancer by neutering pets at a young age, but this is about the limit of our ability to prevent cancer in animals. Therefore, early detection and treatment are the best way to manage cancer in pets.

Help your veterinarian with early detection by alerting him to new lumps and bumps that you find or by reporting any of the signs listed at the end of this article. Also, be sure to do cancer screenings including blood tests, urinalyses and X-rays as your pet approaches and passes 10 years.

Different types of cancer require different therapies. Often simple surgical removal is all that is necessary to cure your pet.

Other times, multiple surgeries, chemotherapy, radiation, cryosurgery (freezing), hyperthermia (heating the tissue) or immunotherapy is necessary. Once you have a diagnosis and your veterinarian has determined how extensive the cancer is, you can discuss all the different treatment options.

In some cases, your vet might refer you to our local board-certified veterinary oncologist. Other times, he might recommend a local internist or surgeon. In rare cases, a pet might even go to the North Carolina School of Veterinary Medicine or to the University of Georgia for extensive care.

The success of cancer treatment depends on the type of cancer and the level of therapy chosen. One thing to remember is that veterinarians agree about one thing: Our job is to help pets feel better for as long as possible.

So if your veterinarian is talking about chemotherapy, radiation or other scary-sounding procedures, don't immediately refuse these based on your experience with them in humans. If drugs or radiation seem to be making your pet feel sicker, the doses will be cut back or discontinued. The reason for this is that we don't necessarily need a cure to get a good quality of life for another year or so.

In people, we usually are trying to achieve a cure so

that a person might live another 20 years. This isn't the case in dogs, so our approach is different.

10 signs of cancer in pets

(Reprinted from the American Veterinary Medical Association Web site at www.avma.org.)

— Abnormal swellings that persist or continue to grow.

— Sores that do not heal.

— Weight loss.

— Loss of appetite.

— Bleeding or discharge from any body opening.

— Offensive odor.

— Difficulty eating or swallowing.

— Hesitation to exercise or loss of stamina.

— Persistent lameness or stiffness.

— Difficulty breathing, urinating or defecating.

Last year, the Morris Animal Foundation launched a $30 million effort to cure canine cancer. It points out that cancer in pets strongly resembles cancer in children. Therefore, pediatric oncologists are excited about foundation funding for clinical trials in pets that could lead to cures for children.

Since one in four dogs will die from cancer, animal enthusiasts out there might be curious about the Morris foundation. If you are interested in donating or simply finding out more about cancer and the foundation's efforts, visit curecaninecancer.org or www.morrisanimalfoundation.org.

Dr. Katherine A. Saenger owns the Bees Ferry Veterinary Hospital and Boarding Kennel. Send questions to her at vetsaenger@bellsouth.net or visit www.beesferry.com.