What is Lymphoma?

Lymphoma is one of the most common cancers seen in dogs. Although there are breeds that appear to be at
increased risk for this disease, lymphoma can affect any dog of any breed at any age. It accounts for 10-20% of all
cancers in dogs.

In a healthy animal, the lymphoid system is an important part of the body’s immune system defense against infectious
agents such as viruses and bacteria. Lymphoid tissue normally is found in many different parts of the body including
lymph nodes, liver, spleen, gastrointestinal tract and skin. Lymphosarcoma is classified according to the location in
the body in which the cancer begins.

Why Lymphoma can attack your Pet?
environmental factors such as exposure to
pesticides (especially herbicide 2,3-D) or strong magnetic fields increase the incidence, but there is currently no strong proof of this. There is also
some evidence of a possible genetic correlation, but further studies need to be performed to determine the exact risk factors involved in canine
lymphoma.

Symptoms

Most of the time, lymphoma appears as “swollen glands� (lymph nodes) that can be seen or felt under the neck, in front of the shoulders, or behind
the knee. Occasionally, lymphoma can affect lymph nodes that are not visible or palpable from outside the body, such as those inside the chest or in
the abdomen. Other symptoms include vomiting, diarrhea, loss of appetite, weight loss, lethargy, difficulty breathing and increased thirst or
urinations. Cutaneous lymphosarcoma can cause redness or flakiness of the skin, ulceration (especially near the lips and on the footpads),
itchiness or lumps in the skin. Clinical signs will vary depending on the stage of the disease, volume of tumor and anatomic location of the
lymphoma.

Treatment

Lymphoma is a very treatable, but not yet curable disease. The usual treatment for lymphoma in the dog consists of chemotherapy. However, there
are various subtypes of lymphoma that exhibit different behaviors, and some of the more aggressive types are unresponsive to any available
treatment. Lymphoma is considered a systemic disease, which makes surgery and radiation impractical and ineffective. There are numerous
chemotherapy protocols and drugs that are currently being used to treat lymphoma. Lymphoma is such a common malignancy in humans that there
are always new drugs, new protocols and experimental therapy that are being used. Please consult your veterinarian for the most appropriate and
current protocol for your dog.

The chemotherapy treatment usually consists of a combination of oral and injectable drugs given on a frequent basis. The exact treatment protocol
will vary depending on the veterinarian and financial resources of the dog’s family. Below are some common protocols available for treatment after
the initial diagnosis of lymphoma.

Multi-drug protocol : Treatment consists of the use of several chemotherapy drugs (prednisone, L-asparaginase [elspar], vincristine,
cyclophosphamide [cytoxan] and doxorubicin [adriamycin]). Weekly chemotherapy treatments are given for approximately 8 weeks. The treatments
are then spaced to every 2 weeks to complete a total of 6 months of treatment. The average survival time for patients with stage IIIa or IVa lymphoma
treated with this protocol is 1 and 1/2 years.

Doxorubicin alone : The patient is treated with a total of 5 treatments of doxorubicin at 3-week intervals. The average survival time with this approach
is 10-11 months.

COP: This protocol involves a combination of cyclophosphamide in tablet form, vincristine and prednisone. 4 weekly intravenous injections of
vincristine are given, followed by injections at 3-week intervals to complete 6 months of treatment. Cyclophosphamide is given over 4 days every 3
weeks (4 days on; 17 days off). Prednisone is given daily for 6 months. The average survival time with this protocol is reported as 8-10 months.

Prednisone alone : This medication is a steroid and can be given in pill form daily at home. The average survival time for patients with lymphoma
treated with prednisone only is 60 days.