Lyphoma in Dogs- Causes, Symptoms and Treatment for Canine Lyphoma

Lymphoma (called Lymphosarcoma or Malignant Lymphoma) is one of the most common forms of cancer in dogs. There are between 1 to 5 cases per 10,000 of all dogs per year. Lymphoma in dogs is a common cancer of lymphocytes. Between 15% and 20% of malignant tumors in dogs are lymphomas. Lymphomas may appear in the lymph nodes, spleen or liver, and other organs. The cancer is usually aggressive and if left untreated, can cause to a high mortality. Treatment with chemotherapy has become very successful, adding months and sometimes years to the dog's life.
Symptoms of Canine Lymphoma
The symptoms of lymphoma in dogs usually commonly mimic the symptoms of many other diseases or disorders. Almost owners of dogs with multicentric or disseminated lymphoma first find pronounced enlargement of the lymph nodes on the underside of their dog’s neck or beneath and slightly behind the chin. These include the submandibular lymph nodes (the mandible is the lower jaw bone). Affected dogs usually do not seem painful when their submandibular lymph nodes are palpated and show no other unusual symptoms. Some other signs that owners could notice include one or more of the following:
+Depression

Lyphoma in Dogs
photo by: veterinarycancer.com

+Lethargy (profound)                      
+Exercise intolerance
+Fever
+Dehydration
+Weight loss
+Loss of appetite
+Vomiting
+Diarrhea
+Constipation
+Dark tarry stool (melena; digested blood showing up in the stool)
+Distended abdomen
+Abdominal discomfort
+Increased thirst and intake of water (polydypsia)
+Increased volume of urinate (polyuria)
+Cough
+Difficulty breathing
+Difficulty swallowing
+Drooling
+Skin nodules and masses (single or multiple)
+Skin scaling
+Bruised or ulcerated skin lesions
+Hair loss (alopecia; uncommon)
+Itchiness (pruritis; uncommon)
Diagnosis
You will need to give your veterinarian a thorough history of your dog's health and onset of symptoms. The blood tests may reveal anemia, abnormally low amounts of lymphocytes in the blood (lymphopenia), an abnormally high amount of neutrophils (a type of white blood cell) in the blood (neutrophilia), an abnormally high amount of monocyts (a type of white blood cell) in the blood, and abnormally low amounts of platelets (cells that are important in blood clotting), a condition named thrombocytopenia. The biochemistry profile could show abnormally high amounts of liver enzymes and calcium, a frequent finding with lymphomas. Urinalysis results are often found to be at normal levels in these patients.
Treatment for Canine Lymphoma
The treatment approach is determined by the stage of the disease. In the absence of treatment, almost of the dogs with lymphoma succumb to the disease in 4-6 weeks. The treatment for lymphoma in the dog consists of chemotherapy. Lymphoma is know as a systemic disease, making surgery and radiation impractical and ineffective. There may be a wide variety of chemotherapy protocols and drugs that are currently being used to treat lymphoma. The treatment commonly consists of a combination of oral and injectable drugs given on a weekly basis. Some other commonly used drugs include cyclophosphamide, vincristine or doxorubicin, and prednisone.  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. While most veterinarians can administer the treatment protocols, owners of a dog with lymphoma could initially want to look for a consultation with a veterinary oncologist to inform themselves of any new treatment recommendations.