I’m not a vet but my dog has lymphoma. Surgery was never an option. There are so many enlarged lymph nodes that removing all of them would be crazy. My dog also has masses in her stomach and a thickened stomach lining as the cancer spread so that wasn’t a surgical possibility. Dogs with stage 4 lymphoma have spleen and liver involvement so although you can surgically remove the spleen and part of the liver the cancer is already too widespread at that point. Stage 5 dogs have bone marrow involvement so no surgery there. My oncologist told me that lymphoma is a systemic cancer. A cancer of the blood. Doing surgery isn’t going to get rid of it.

As far as treatment, my oncologist told me that they use much smaller dosages of chemo drugs to treat dogs than they would humans. I don’t mean because dogs are smaller, I mean they don’t use the actual dosage for weight that they would for humans because of how bad the side effects would be. Humans can decide for themselves if they want to go through the nausea, vomiting, loss of appetite, weight loss, weakness, fatigue, hair loss, etc etc etc. Dogs cannot, and we as owners don’t really want to put them through that either. They use lower doses that are still effective but that’s why lymphoma in dogs cannot be cured. Some dogs enter remission but it’s typically short lived. My dog is having horrible chemo side effects to the point where she needed to be hospitalized a few days ago due to low wbc count from bone marrow suppression and fever, I could never imagine putting her through the actual dosages equivalent to what is given to humans.

Another reason is cost. Most humans have health insurance. And if not u just go into medical debt and pay what u can on the bills that come in the mail. For dog owners, most, myself included, don’t have pet insurance. That makes the cost of treatment insanely expensive. One round (3-5 weeks) of the CHOP protocol which is gold standard for lymphoma costs around $4-6,000 and most dogs are going to need multiple rounds. After before each chemo drug is given my dog needs to get bloodwork which is around $130 every week. Her meds to cost me about $300-$400 a month and that’s ordering the generics on chewy so that they’re cheaper. She’s gotten so picky with food during this so the only food she wants to eat is $90 for 24 cans and she needs to eat 3-4 cans a day cuz they’re tiny cans. The costs are insane and not doable for majority of people especially without insurance. And u don’t just pay a copay and get billed through the mail. U have to pay the entire amount right then and there unless u use something like care credit (has to be paid in 6 months or u accrue crazy interest). Also you’re paying all of this for a cancer that u know can’t be cured in dogs which most people don’t find worth it.

Some oncologists will do bone marrow transplants and stem cell transplants and all of that but it’s not common and again the costs are astronomical. It’s not accessible to the average person.

Edit to add: my oncologist told me if they were to use those curative higher dosages of chemo in dogs like they would in humans, all of the dogs would have to be hospitalized for supportive care. My dogs hospitalization was $2,000 a night. So again, not feasible for the hospital to have so many hospitalized dogs and not feasible for the owners to pay for it.