Lymphosarcoma in Ferrets
A type of white blood cell, lymphocytes play an important and integral role in the body's defenses. When a cancer develops in the lympocyte cells of the immune system, it is referred to as lymphoma, or lymphosarcoma. This can eventually affect the blood, lymph and immune systems, as well as the gastrointestinal and respiratory systems.
Lymphoma is one of the most common diseases seen in pet ferrets. In fact, it is the third most common tumor affecting ferrets, often occurring between the ages of two and five. However, middle-aged ferrets may be asymptomatic (sometimes for years), or have nonspecific signs that wax and wane.
Symptoms and Types
Symptoms are variable depending upon the location and stage of tumor, but generally, they include loss of appetite (anorexia), weakness, lethargy, and weight loss. For example:
- Multicentric—possibly no signs in early stages; generalized, painless enlarged lymphs most common; may note distended abdomen; anorexia, weight loss, and depression with progression of disease.
- Gastrointestinal—anorexia, weight loss, lethargy, vomiting, diarrhea, abdominal discomfort, tarry stools, urgent desire to defecate.
- Mediastinal (mid-chest)—seen most often in younger ferrets—anorexia; weight loss; drooling; labored breathing; regurgitation; exercise intolerance; coughing; difficulty swallowing.
- Cutaneous (skin)—solitary or multiple masses; lesions may be pustular with thickening and crusting or ulcerating.
- Solitary form—depends on location; spleen: abdominal distention, discomfort; cancer in the area of the eyes: facial deformity, protrusion of the eyeball; spinal cord cancer: quickly progressing posterior partial paralysis may be seen; kidney: signs of kidney failure.
Although the cause is still unknown, some suspect viruses to be a factor. Exposure to other ferrets with the disease may be another risk factor.
You will need to give your veterinarian a thorough history of your ferret'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 ferret. Routine laboratory testing includes a complete blood count and urinalysis.
Diagnostic imaging, including X-rays and ultrasound, are often used to evaluate the size of regional lymph nodes. Your veterinarian may even recommend taking bone marrow samples, so that they can be sent to a veterinary pathologist for further evaluation and to determine the extent of disease.
Many ferrets with lymphoma are asymptomatic, and the diagnosis is often incidental. It can be difficult to predict whether treatment is warranted in these cases. Many ferrets will remain asymptomatic for years, requiring no treatment. Others, meanwhile, may show signs of disease that are cyclic or even waning with or without treatment, making evaluation of treatment success difficult.
Typically, treatment is indicated in young ferrets with aggressive cancer, or in middle-aged to older ferrets with clinical signs attributable to cancer. Older, debilitated ferrets are more likely to develop serious side effects to chemotherapy. Debilitated, anorectic, or dehydrated ferrets will be hospitalized for intravenous chemotherapy. There is also a possibility that surgery may be required to relieve intestinal obstructions, remove solitary masses, and to obtain specimens.
Living and Management
After remission, some protocols will allow you to administer drugs orally at home. You will need to wear latex gloves when administering these drugs.