The big problem with big lymph nodes: understanding canine lymphoma.
Lymphoma is one of the most common cancers in dogs. The most familiar sign is the sudden appearance of enlarged lymph nodes — often under the chin, above the shoulder blades, or behind the knees — in a dog who otherwise seems to feel fine.
If you feel new lumps under your dog’s jaw, above the shoulders, or behind the knees, have them evaluated soon — even if your dog seems normal otherwise. Dogs who begin lymphoma treatment before they feel sick often respond better. Call Dogwood at (404) 609-1234 to schedule an oncology consult with Dr. Laura Venner.
Lymphoma describes a diverse group of cancers in dogs that arise from a white blood cell called a lymphocyte. Normally, lymphocytes function within the immune system to protect the body from infection and coordinate inflammation. When they become cancerous, they can spread throughout the body via the lymphatic system — often silently at first.
How canine lymphoma typically shows up.
The most common presentation of lymphoma in dogs is enlarged lymph nodes underneath the chin, above the shoulder blades, and behind the knees. Other presentations can occur that are more localized to the gastrointestinal tract, skin, kidneys, tonsils, or central nervous system, but the classic case is a dog whose owner suddenly notices new lumps on both sides of the neck or body.
Most dogs do not feel sick at diagnosis. Some may have subtle signs such as a decreased appetite, mild diarrhea, or occasional vomiting. Sometimes routine bloodwork tips us off first — picking up an elevated blood calcium level (hypercalcemia) or an increased lymphocyte count. Even if a dog is not feeling sick from lymphoma, we still recommend seeing an oncologist promptly, because dogs who begin treatment before feeling sick tend to respond better.
- Enlarged lymph nodes under the jaw, above the shoulders, or behind the knees
- May feel bilateral (both sides) and non-painful
- Often occurs in a dog who seems otherwise well
- Sometimes accompanied by decreased appetite, mild GI signs, or increased thirst
- Hypercalcemia or elevated lymphocyte count may be found on routine bloodwork
B cell vs T cell — why immunophenotyping matters.
Lymphoma in dogs is commonly characterized by the type of lymphocyte causing the cancer — a feature called the immunophenotype. The most common immunophenotypes in dogs are B lymphocytes (which cause B cell lymphoma) and T lymphocytes (which cause T cell lymphoma).
Immunophenotyping is determined through a test called flow cytometry, performed on a lymph node aspirate. Knowing whether your dog has B cell or T cell lymphoma helps us tailor a chemotherapy protocol that is best suited for your dog’s specific disease, and it helps us give you a more accurate prognosis. B cell lymphoma is generally more chemotherapy-responsive than T cell lymphoma, though both are treatable.
Chemotherapy for canine lymphoma.
Treatment for lymphoma commonly involves chemotherapy. While chemotherapy is not well tolerated in people, it is generally well tolerated in dogs. Only about 20% of patients experience side effects, and most of those side effects can be treated with anti-nausea and anti-diarrhea medications at home. We do not expect dogs on chemotherapy to experience major lifestyle changes, and our oncology team may adjust chemotherapy dosing to ensure your dog’s quality of life stays optimal during treatment.
There are several chemotherapy protocols available to treat canine lymphoma. The Dogwood Oncology team will tailor a treatment protocol that fits your dog’s specific disease, your family’s goals, and your dog’s overall health — from multi-agent CHOP-based protocols to single-agent options for families who want a less intensive schedule.
The Dogwood advantage. Cancer rarely fits into one specialty. At Dogwood, lymphoma cases have the support of on-site CT and ultrasound, an in-house lab for rapid response to bloodwork changes, board-certified critical care specialists for any patient who needs closer monitoring, and a board-certified veterinary internist to help manage related conditions — all in the same building, on the same shared record.
Frequently asked questions
Which dogs are most at risk for developing lymphoma?
Any age or breed of dog can develop lymphoma, but certain breeds are at higher risk, including Boxers, Golden Retrievers, Pit Bulls, and Rottweilers. Lymphoma most commonly appears in middle-aged to older dogs, though younger dogs can be affected as well.
Can lymphoma be treated without chemotherapy?
There is a newer medication recently approved for the treatment of lymphoma in dogs called Laverdia®. Instead of targeting fast-growing cells like traditional chemotherapies, this medication works by targeting molecule export from the nucleus into the cell. Treatment with Laverdia® typically holds the disease at bay for a shorter period of time than multi-agent chemotherapy but can be a good option for families who want to avoid IV chemotherapy visits.
Will my dog lose their hair during chemotherapy treatment?
Most dogs undergoing chemotherapy will not lose their fur. However, certain breeds are more susceptible to hair thinning or loss during treatment, including Maltese, Shih Tzu, Old English Sheepdogs, and Poodles.
Can treatment cure canine lymphoma?
Chemotherapy commonly achieves remission for lymphoma, but rarely cures it. Most dogs can achieve a durable remission — often lasting many months to a year or more — during which they feel well and live comfortably. Some dogs achieve second and third remissions with rescue protocols when the first remission ends.
Do I need a referral to see a veterinary oncologist?
A referral from your primary veterinarian is helpful because it lets us coordinate records and prior workup, but it isn’t required. Families can request an oncology consult directly with our team.