Cancer of the Lymphocytes in Dogs
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 integral role in the body's defenses.
There are two forms of lymphocytes: B and T cells. Lymphoma may involve neoplastic proliferation of T or B, or non-B/non-T type lymphocytes, occurring primarily in the bone marrow, lymph nodes, and visceral organs. But mostly cases involving B-lymphocytes are seen in dogs.
Although rare in dogs, lymphoma is more prevalent in Boxers, golden retrievers, saint bernard, basset hounds, Airedale terriers, Scottish terriers, and bulldogs.
Symptoms and Types
Symptoms are variable depending upon the location and stage of tumor, but generally, the symptoms that are common in all forms of lymphoma are lack of appetite (anorexia), weakness, lethargy, and weight loss.
The exact cause is still unknown.
You will need to give your veterinarian a thorough history of your dog's health and onset of symptoms. The history and details you provide may give your veterinarian clues as to which organs are being primarily affected. Knowing the starting point can make diagnosis that much easier to pinpoint. Once the initial history has been taken, your veterinarian will perform a complete physical examination on your dog. Routine laboratory testing includes a complete blood count, biochemistry profile, and urinalysis.
The blood tests may reveal anemia, abnormally low levels of lymphocytes in the blood (lymphopenia), an abnormally high number of neutrophils (a type of white blood cell) in the blood (neutrophilia), an abnormally high number of monocyts (a type of white blood cell) in the blood, and abnormally low numbers of platelets (cells that are important in blood clotting), a condition called thrombocytopenia. The biochemistry profile may show abnormally high levels of liver enzymes and calcium, a common finding with lymphomas. Urinalysis results are usually found to be at normal levels in these patients.
More specific testing may be required for a confirmatory diagnosis. Diagnostic imaging, including X-rays and ultrasound, are often used to evaluate the size of regional lymph nodes. Your veterinarian will take bone marrow samples to be sent to a veterinary pathologist for further evaluation and to determine the extent of disease.
There is no cure for this disease and relapses are common after therapy. Chemotherapy and radiotherapy are commonly used for treatment in lymphoma animal patients. Use of chemotherapy alone or with radiation therapy will be decided by your veterinary oncologist based on the stage of the disease, the age of your dog, and your dog's overall well-being.
In dehydrated patients, fluid therapy is given to stabilize the body fluids. In case of abnormal fluid accumulation in the chest or abdomen, your veterinarian will remove the accumulated fluid. Unfortunately, relapses are common after chemotherapy and it is rarely found to have long term curative value in most affected patients. The ultimate goal of chemotherapy remains to improve the quality of life in affected patients.
Living and Management
Unfortunately there is no cure available for this disease. The only resolution in some cases is to provide extra care to improve the quality of life in affected animals. Many side-effects are seen with chemotherapy and you should talk to a veterinary oncologist for best recommendations before deciding on this type of therapy. Chemotherapeutic drugs are highly toxic to different body systems and various complications are seen during and after treatment.
Chemotherapy is also potentially hazardous for human beings, therefore you should talk to the veterinary oncologist about safe handling and administration of chemotherapeutic medicines at home. Basic precautions include wearing latex gloves before drug administration.
Regular monitoring and checkups are required for evaluating the the patient's progress. Regular blood testing, along with cardiac and other body system evaluation is required during treatment. You will need to visit your veterinarian at regular intervals for follow-ups and at each visit your veterinarian will evaluate your dog’s response to treatment and adjust it as necessary. In case of serious complications, your veterinarian may reduce dosages or stop the treatment altogether.
During chemotherapy, patients are more prone to various infections, which can quickly become complicated, so you will need to watch your dog for any signs of infection. Call your veterinarian immediately if you observe any untoward symptom in your dog. Do not ever increase or reduce the dosage of drugs without prior consulting with your veterinarian. If pain medications have been prescribed, use them with caution and follow all directions carefully, making sure that all members of the home are familiar with the medication schedule; one of the most preventable accidents with pets is overdose of medication.