Lymphoma in dogs, also known as lymphosarcoma and lymphocytic leukemia, is a type of cancer that affects cells of the lymphatic system. The disease is not common, and it can affect male and female dogs of all breeds. In some cases, there may be a genetic link to the cause of the disease as Boxers, Golden Retrievers, and Old English Sheepdogs are affected by the disease at a higher rate than other breeds.
A study from Italy suggests that canine malignant lymphoma is very slightly associated with residence in urban industrial areas, and with the use of paints or solvents by the owner. That said more detailed studies need to be performed before and firm conclusions can be reached.
The clinical signs that pet owners might see arising from lymphoma are nonspecific and varied and can be caused by many other illnesses or diseases. These signs include depression, fever, weight loss, loss of appetite and vomiting. What most owners first notice are firm, painless and markedly enlarged lymph nodes
Biopsy of affected lymph nodes or organs confirms the diagnosis of lymphoma in dogs, although a needle aspiration of an affected lymph node can increase suspicion of the disease. X-rays, ultrasound, blood analysis, and bone marrow biopsy reveal other locations of the cancer in dogs. The stage of the disease is important to treatment and prognosis.
Chemotherapy is the go-to treatment for canine lymphoma, because the cancer cells are distributed throughout the body, and so are the drugs used to attack them. The objective goal is complete remission of the cancer. Subjectively, the goal is to maintain a top quality of life for the patient.