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LennyDVM, Veterinarian
Category: Dog
Satisfied Customers: 548
Experience:  30 years as owner of a mobile practice treating dogs, cats, horses and other pets.
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Can dogs pass virus that mimics lymph cancer?

Customer Question

My bassett, 4 moths ago, had huge swollen lymph nodes vet said she had cancer with no test being done. Her face became so swollen she looked like a different dog.

Vet recommended we put her to sleep. Not wanting her to suffer we did. Now my dachshund has huge swollen lymph nodes. Vet said it also looks like cancer, but agreed to give antibiotics for 10 days.

My question is can dogs pass a virus among themselves that mimic lymph cancer? I just don't understand how this is affecting 2 of my dogs in a matter of months.

Submitted: 6 years ago.
Category: Dog
Expert:  LennyDVM replied 6 years ago.

Lymphoma (cancer of lymph cells) is a very common cancer in dogs although it usually affects middle aged to older animals. I've listed other possible causes of enlarged nodes below.

Lymphoma is easy to diagnose. A sample of the lymph node is taken by putting a syringe with a needle into the node and drawing a small sample of cells into the syringe. This is smeared on a microscope slide and sent to a laboratory for analysis. Some vets can stain the slide and look at it under a microscope without sending it out. This gets immediate confirmation of lymphoma if that is the problem. This does not require anesthesia or tranquilization and the majority of dogs do not mind the procedure.

The differential diagnosis for swollen lymph nodes includes:

  • Lymphoma or lymphosarcoma. This is the most common cause of swelling of multiple lymph nodes. Often the nodes behind the jaw, in front of the shoulders and behind the stifle/know of the hind legs are enlarged. Treatment generally results in months to years of remission with good quality of life. It can be expensive.
  • Reactive swelling as part of a general or local immune response (e.g. allergic reaction)
  • Lymphadenitis from inflammation or infection (bacterial, fungal)
  • Sterile granulomatous lymphadenopathy where apparent infectious agent is not involved
  • Mineral-associated granulomatous lymphadenopathy has crystalline/mineral based material within nodes
  • Metastatic cancer from a region of the body that drains into the swollen nodes
  • Lymph node hemorrhage, infarction or edema
Customer: replied 6 years ago.
I was wondering, since it hit two of my dogs in a matter of months and if it isn't cancer, could a virus cause this and could the dogs infect each other. If it is cancer do you think there is something in their environment that caused it? I have two other dogs and I fear for their health. Thanks for your help
Expert:  LennyDVM replied 6 years ago.

I understand your concern and apologize for not answering this part of your original question. My answer is a bit convoluted. In short, lymphoma (cancer) in dogs does not appear to be contagious; however, there are other causes of swollen lymph nodes that are infectious if not contagious (passing from animal to animal).

Lymphoma is caused by or associated with a viral infection in some species (cats, cattle, chickens, mice, humans), but this has not been shown in dogs. Lymphoma is very common, but the incidence of lymphoma is not increased in dogs who live with affected dogs. There is evidence of a genetic predisposition in some dogs.

Some studies show a relationship between chronic inflammation and lymphoma. For example B cell lymphoma in a dog in one report may have been related to chronic infection with ehrlichia and histoplasma.

Histoplasmosis and Valley fever are fungi that can cause swollen lymph nodes. Infection results from contact with spores in soil. It is not generally considered contagious from animal to animal, but animals in the same household may be exposed to the same source. Richetsial infections (Ehrlichiosis, Rocky Mountain spotted fever), Salmon poisoning, cat scratch disease... etc.

Because lymph node enlargement can be caused by diseases (given in my first response) besides lymphoma, it makes sense to diagnose the cause of the swollen lymph nodes in your dog that is currently affected. An aspirate as described earlier would be a reasonable way to start. Make sure the lab doing the analysis for fungal and bacterial infections. If an aspirate does not provide enough material, a lymph node biopsy or removal with submission for histopathology would provide the needed material.

LennyDVM, Veterinarian
Category: Dog
Satisfied Customers: 548
Experience: 30 years as owner of a mobile practice treating dogs, cats, horses and other pets.
LennyDVM and other Dog Specialists are ready to help you
Customer: replied 6 years ago.

Thank you for your response that explanation does help. He is going to have a biopsy Friday. I hope its good news, I haven't gotten over the loss of our other dog yet.

Expert:  LennyDVM replied 6 years ago.

I'd appreciate hearing the outcome of the biopsy. I don't know if you can add it to this thread or not.

My thoughts are with you and your pups. I know all too well how hard it is to lose pupper friends.

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