Nov 3, Most of us have heard of lymphoma. It is a common cancer in people and dogs, which does not make it any less terrifying for dog owners. Unfortunately, the cause of lymphoma in dogs is not known. Although several possible causes such as viruses, bacteria, chemical exposure, and physical factors. Lymphoma is generally seen in middle aged to older dogs (median age, years). Generic causes- The etiology is largely unknown and likely multi factorial.
Lymphoma What Dogs? Causes in
Most dogs treated with chemotherapy will experience a remission, a period in which there is no detectable cancer and the dog feels well. Remission times are variable, but most dogs with the lymph node forms of LSA will have initial remissions lasting in the range of months before evidence of the tumor is seen again; second remissions can be achieved in many of these dogs, but any subsequent remission is expected to be shorter in duration than the first remission.
Survival times for most dogs treated with combination chemotherapy protocols are in the range of approximately 1 year. And even though an individual dog will have received a lot of chemotherapy over that year, their quality of lfe is generally very good. Statistics, while useful, can never predict how an individual dog will fare with or without specific treatment.
New protocols are tried with great regularity in canine lymphoma but results have been similar with each drug regime investigated.
Most likely our survivals will always be similar until we either accept greater toxicity meaning most dogs will be very sick from the treatment and some may even die , or a completely novel treatment is invented. Using half or whole body radiation therapy may prove helpful. The development an antibody specific for dog lymphoma, which could recognize all dog lymphomas and yet no normal lymphocytes, and be attached to a toxin or other cell killing mechanism, is a far off dream.
LSA is one of the most chemotherapy-responsive tumors seen in veterinary medicine, and most dogs tolerate chemotherapy very well with minimal impact on their quality of life. If you notice fast growing lumps on your dog that seem to be in the area of the major joints at the neck, in front of the shoulders, in the armpits, at the back of the knees or in the groin have your dog examined soon by a veterinarian even if he feels well. College of Veterinary Medicine.
Lymph node staging Stage I: Biological behavior of LSA LSA is viewed as a systemic disease, and as such is not really viewed to "spread" to other organs.
Clinical staging determination of the extent of the tumor Because of the organs that LSA commonly involves, staging a dog with a LSA can involve aspiration of one or more lymph nodes, thoracic radiographs abdominal radiographs or ultrasound to look for big nodes in the abdomen and to look at the liver and spleen , or bone marrow examination. Treatment options The mainstay of treatment of LSA is administration of chemotherapy drugs; the best responses in terms of length of tumor control and survival are generally seen with protocols that entail administration of more than one chemotherapy drug, although there are approaches that involve administration of a single drug.
Prognosis The prognosis of dogs with LSA is highly variable, and depends on the clinical stage ill dogs fare more poorly than dogs that feel well, and dogs with Stage V disease are generally considered to have a poorer prognosis , the type of tumor dogs with B-cell LSA usually do better than dogs with T-cell LSA. Key points LSA is one of the most chemotherapy-responsive tumors seen in veterinary medicine, and most dogs tolerate chemotherapy very well with minimal impact on their quality of life.
Most types of lymphoma are high-grade and involve T cells or B cells. In dogs, lymphoma has been classically characterized by body locations in which they occur: An early sign of multicentric lymphoma is the rapid and nonpainful enlargement of lymph nodes, which may become 3 to 10 times their normal size. In addition to this, cancerous lymphocytes may move into internal organs including the spleen, liver, bone marrow, and other sites.
Late in the course of disease, when there are multiple, large tumors, dogs may show general signs of illness, including lack of energy, weakness, fever, loss of appetite, and dehydration. Dogs with this form of the disease may have signs related to stomach upset, such as vomiting and abdominal pain.
When the disease affects most of the intestinal tract, dogs may have devastating signs, such as loss of appetite, vomiting, diarrhea, and continued weight loss because they cannot digest food properly. Mediastinal lymphoma is also uncommon. Dogs with this form of the disease may have an enlarged thymus, lymph nodes, or both. As the disease advances, signs may include trouble breathing as fluid builds up in the chest and puts pressure on the lungs.
The tumor may block the vein that routes blood from the upper part of the body into the heart. In addition to signs related to breathing, some dogs with mediastinal lymphoma pass large amounts of urine and drink more than normal. The medical problems associated with extranodal lymphoma vary and depend on which organ is affected. Skin lymphoma may appear as single, raised, slow-healing sores or widespread, scaly regions.
Signs of lymphoma at other extranodal sites include difficulty breathing lungs , kidney failure kidneys , blindness eyes , seizures central nervous system , and bone fractures and pain bone.
These tumors develop slowly, and dogs may not show any signs of the disease. Canine lymphoma is often relatively easy to diagnose by taking a small sample of tissue or cells from the affected organ system. In dogs with multicentric lymphoma, a needle biopsy of enlarged lymph nodes usually provides enough cells to confirm the diagnosis.
Specialized tests can then help determine the type of lymphoma, which cell types are affected, and the expected outcome. Individual treatment plans vary with respect to the drugs used, dosage, and frequency and duration of treatment. With chemotherapy, the expected survival time for dogs with B-cell lymphoma is about 12 months.
For dogs with T-cell lymphoma, expected survival times are shorter 6 months. Dogs that do not respond to the usual drugs may improve when other treatment plans are used. These alternate plans may include other drugs or radiation. In recent years, treatment has included both initial and longterm medications.
New Research Shows a Genetic Cause of Lymphoma in Dogs
Malignant lymphoma is a common cancer in dogs. It is a progressive, deadly disease caused by the harmful growth of lymphocytes. Lymphoma most commonly. Lymphoma is a type of cancer that originates in the lymphocyte cells of the immune system. A type of white blood cell, lymphocytes play an important and. By Joanne Intile, DACVIM. Lymphoma is a blood-borne cancer of lymphocytes, which are a specific type of white blood cell. It is the most common cancer.