Lymphoma in dogs:
Sometimes a dog owner will bring in a dog ... usually middle aged or older ... any breed, but often a Golden Retriever ...
Sometimes these dogs are sick and other times not, but your vet notices that multiple lymph nodes are enlarged. We're all trained to check for this.
Your vet will strongly suspect the cancer known as Lymphoma ... something we see all too often in both cats and dogs.
With blood work, urinalysis, radiographs, ultrasound, lymph node aspirates, and especially biopsy we can confirm the suspected diagnosis as well as determine to some degree the extent of the disease. Often multiple organs are affected.
This is a serious disease; without treatment, patients often live only a few months after diagnosis. But good news; treatment is often successful.
I'm sorry, but once we get a diagnosis I don't know a whole lot about the treatment of this disease. I refer these cases to our cancer specialist in the big city of Greenville. I do, however have a client information sheet copied below about treating Lymphoma.
Lymphoma in cats:
This is a pretty common disease in middle aged and older cats.
Like dogs with lymphoma, cats with lymphoma have enlarged lymph nodes, and may have actual masses in the abdomen, but the most common form in cats is a diffuse cancer of the intestines.
Once again, treating lymphoma in cats is above my level of expertise so I refer patients with suspected lymphoma to a specialist. They will confirm the diagnosis and make sure I haven't mistaken this disease with inflammatory bowel syndrome. Treatment may or may not be successful.
From The TEXTBOOK OF VETERINARY INTERNAL MEDICINE Client Information Series about the treatment of lymphoma:
Susan A. Kraegel
Lymphoma is a cancer of a specific white blood cell called the lymphocyte.
Lymphocytes are found throughout the body in blood and tissues and act to protect the body from infection. Lymphocytes are the major cells found in lymph nodes or "glands." In lymphoma, the cancer cells invade and destroy normal tissues. The most common site for lymphoma is the lymph nodes, but lymphoma cells, like lymphocytes, can grow anywhere in the body. In most dogs and cats with lymphoma, the cancer cells are present in multiple lymph nodes and tissues.
Chemotherapy is the treatment of choice for almost every dog and cat with lymphoma. Chemotherapy is the administration of drugs by injection or by mouth to kill cancer cells. The chemotherapeutic drug circulates throughout the body. This is important for lymphoma because the cancer cells are in many places at once. Surgery and radiation therapy are less useful in lymphoma because these treatment methods attack cancer cells at only one site.
The goal of chemotherapy for animals with lymphoma is to induce a complete "remission" by killing most of the cancer cells. "Remission" means that all symptoms of the cancer have temporarily disappeared. Animals with Iymphoma that are in complete remission look like normal animals by all tests. They do not have any signs of cancer, and all masses or lumps have disappeared. They eat, drink, and run just as they did before they developed cancer. Some of the cancer cells do survive in an animal in complete remission, but the numbers are too small to detect. Eventually, these few cells will grow and the cancer will become evident again. When this happens the animal is said to be "out of remission." Sometimes a second remission can be achieved with additional chemotherapy. Eventually, the cancer cells will become resistant or insensitive to all drugs and cause the dog or cat to die.
Veterinarians use many different drugs and drug combinations called "protocols" to treat lymphoma in dogs and cats. No one knows the "best" treatment, and many protocols give similar results. In general, the longest survival times are reported for protocols that use a combination of drugs and include more expensive drugs.
Although chemotherapy does not cure dogs and cats with Iymphoma, in most it does extend the quantity and quality of life. About 80 to 90 per cent of dogs with lymphoma attain a complete remission with an average survival of 1 year, and 25 per cent of dogs live 2 years. For cats, the remission rate is lower, with about 50 per cent attaining a complete remission, but cats who achieve only partial remission also feel better according to owners. The average survival for cats is 7 to 10 months.
Veterinarians use chemotherapy to give dogs and cats with lymphoma a good quality of life with minimal side effects. Most dogs and cats with lymphoma feel good even though they are receiving chemotherapy. The potential for side effects does exist, however, and varies with the protocol used. The most common side effects include decreased energy, decreased appetite, vomiting, and diarrhea.
Occasionally, more severe side effects occur, and in rare cases an animal receiving chemotherapy will die as a result of treatment. Unfortunately, the only way to know whether an animal is going to have a drug reaction is to give the drug. Some animals never get sick during chemotherapy, but others are very sensitive to the drugs. If your pet has a serious reaction, the drugs or doses your pet receives may be individually adjusted to maintain a good quality of life.
As an owner, you can help your pet with lymphoma by watching the pet closely after each treatment. Chemotherapy will suppress your pet's immune system and make him or her more susceptible to infections. These infections generally arise from bacteria that normally live in the intestinal tract and on the skin, not from the environment. Signs of an infection may include loss of appetite, vomiting, diarrhea, decreased activity, or depression. Phone your veterinarian immediately if your pet appears ill while receiving chemotherapy. These signs are usually only brief reactions to the drugs, but prompt treatment can often prevent more serious side effects from developing.