How to recognize the symptoms of lymphoma in dogs, and what to do about it.
Lymphoma is the most common form of cancer found in dogs. This fast-growing malignancy is able to grow wherever there is lymph tissue, which is virtually every organ in the body.
The cancer can be aggressive and, if untreated, has a high mortality rate. However, treatment with chemotherapy can be very successful, adding months and sometimes years to a dog’s life.
Lymphoma in Dogs: Which dogs are at risk?
Any dog, regardless of age, sex or breed can get lymphoma. However, the cancer mainly affects middle aged to older dogs.
Certain breeds also appear to be more prone to the disease, with Golden Retrievers, Boxers, Bull Mastiffs, Bassets, Saint Bernards, Scottish Terriers, Airedales, and Bulldogs, particularly susceptible.
Nobody fully understand why lymphomas form in dogs (or humans for that matter). In cats, it appears to be strongly linked to the feline leukemia virus, but no similar link is apparent in dogs.
There has also been some research that suggests a genetic link.
Symptoms of Lymphoma in Dogs
The symptoms of lymphoma depend on the location of the tumor (or tumors).
Lymphomas that affect the skin present in the form of single or multiple lumps on the skin, or in the mouth. These lumps may be itchy, red and ulcerated.
When the lymphoma occurs in the gastrointestinal tract, it causes vomiting, diarrhea, weight loss, and lack of appetite.
In the chest it creates shortness of breath and muffled heart sounds.
Lymphoma can also occur in the heart, eyes, bone marrow, and the central nervous system.
Lymphoma in Dogs: Diagnosis
The first indication of lymphoma is likely to be one or more lumps just under the skin. If you find these lumps on your dog, even if he shows no sign of illness, take him to the vet immediately.
It may be that they are simply non-malignant lipomas, but if your vet finds that the lymph nodes are enlarged and firm, he’ll have to run some tests.
The next step is an analysis of blood and urine, as well as a biopsy of one or more lymph nodes. X-rays and ultrasound may also be employed.
Lymphoma in Dogs: Treatment
Lymphoma in dogs is treated with chemotherapy as other methods, like surgery and radiation, are ineffective.
The exact treatment protocol will be determined by the veterinarian, but usually consists of a combination of oral and injectable drugs given on a weekly basis. Drugs that are commonly used include cyclophosphamide, vincristine, doxorubicin, and prednisone.
In dogs that receive chemotherapy protocols, life expectancy can be extended by about a year, but rarely longer. Most dogs tolerate chemotherapy well, so the quality of life is quite good while undergoing treatment.
For dogs that do not receive treatment, life expectancy is 4-6 weeks. Oral prednisone therapy may reduce swelling and discomfort, caused by lymphoma in dogs, during this time.
