Dogs and cats are living longer and healthier lives.  As a result, they are becoming more susceptible to diseases more common in later life, such as heart disease and cancer.  Dogs and cats can develop many different types of cancer. Some kinds of cancer are curable, some are treatable, and for some we can only provide reasonable degrees of comfort.

Definition of Cancer
Cancer is an uncontrolled growth of cells on or in the body.  It may invade nearby tissues and/or spread throughout the body via the lymph or blood streams, or both.

Incidence 
The overall incidence increases with age.  After 10 years of age, half of all pet deaths are due to cancer.  Cancer is more common in dogs than in cats.

Ten Warning Signs of Cancer (one or a combination of signs may be evident):

1. Swellings that persist or continue to grow
2. Sores that do not heal
3. Unintentional weight loss
4. Loss of appetite
5. Bleeding or discharge from a body opening
6. An offensive odor
7. Difficult eating or swallowing
8. Hesitation to exercise or loss of stamina
9. Persistent lameness or stiffness
10. Difficulty in breathing, urinating, or defecating.     

Diagnosis 
Blood tests, x-rays, and ultrasonography are among many exams that your veterinarian may perform to find, locate, and assess the possible spread of cancer in your pet.  Locating the growth and performing a biopsy is necessary to determine the exact type of cancer and select the optimal form of treatment.

Treatment 
Each cancer and patient is a unique combination that requires individual decisions and care.  Determining a therapy depends on the type of cancer based on biopsy results, the grade or stage of the cancer, and its location.  Cancer therapy in pets includes surgery, medications (chemotherapy), radiation therapy, and other forms of therapy.

Chemotherapy is used if a cancer cannot be completely removed by surgery or destroyed by radiation.  Some cancers are very responsive to chemotherapy, while others do not respond at all.  Depending on the type of cancer responsive to chemotherapy, different drugs or combinations of drugs are used to reduce the size of the cancer more quickly and to maintain remission as long as possible.  Some medications are injected and some may be given as pills.  Treatments are given on an outpatient basis whenever possible.

Most pets receiving chemotherapy experience minimal side effects.  Some display more energy and an improved appetite. Some drugs can cause nausea, vomiting, or diarrhea, but adverse effects such as these can often be prevented or minimized. Low white blood cells (infection fighters) counts are a more common problem.  Therefore, complete blood counts are determined before chemotherapy.  Chemotherapy baldness is exceptionally uncommon in most pets, although some drugs can cause hair loss in dogs like poodles. Pets receiving chemotherapy should be able to perform and enjoy all of their normal activities.

Not all cancers in pets can be cured, but today, most pets with cancer can be helped to some degree.

For more information, contact your local veterinarian or the MU Veterinary Medical Teaching Hospital 573-882-7821 or visit their web site.