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Cancer, Surgery and Chemotherapy Treatment: What’s Ethical for a Senior Dog?

Double tumor whammy for Denali

Reviewed by Dr. Bill Saxon DVM, DACVIM, DACVECC on Tuesday, August 11, 2015
Posted September 12, 2014 in A Vet's Life

Dr. Phil Zeltzman is a traveling, board-certified surgeon in Allentown, PA. His website is He is the co-author of “Walk a Hound, Lose a Pound” (


Lung Surgery
Denali*, a 14-year-old Shih Tzu, had surgery about six months ago to remove a large lung tumor.

We performed open chest surgery to remove the lung. Denali recovered very well and went home after a couple of days. A week later, the biopsy results confirmed my suspicion: the tumor I had removed was malignant (remove ‘cancerous’) (called bronchoalveolar carcinoma).

Chemotherapy treatment
Denali’s owner was thoroughly dedicated to her dog and elected to do everything she could to increase his longevity, while maintaining his quality of life. She elected chemotherapy. Denali did very well, as many pets do. He went through chemo like a champion.

Six months later, Denali, who was now 15 years old, went to the groomer to get a haircut. She noticed a firm swelling on the right side of his anus. Fortunately, the groomer encouraged Denali's owner to check in with her family veterinarian.

Rectal tumor in a senior dog
The news was not good. A rectal exam revealed that the very firm mass was larger than a cherry (in a Shih Tzu!) and appeared to stem from the anal sac.

Almost invariably, these tumors are cancerous and aggressive. It was actually quite shocking that this cancerous tumor appeared in spite of chemotherapy. But of course, Denali’s chemo was not meant to prevent another type of cancer from popping up. The chemo protocol was designed to help with the lung tumor, not with any other type of cancer.

The ethical dilemma of additional cancer treatment
When I met Denali’s owner, we realized that we were facing a huge ethical dilemma. Was it fair to remove a cancerous tumor that wasn’t causing any problems yet (but shortly would) in a 15-year-old patient?  Was it reasonable to perform another surgery in a cancer survivor who had a lung tumor removed only six months ago? Was it realistic to spend so much money on a geriatric dog?

Were we truly doing this to help the patient? This was really not an easy decision for either one of us to make. Sure, my job is to fix patients, but this was a difficult ethical dilemma. What was I to do?

Denali’s owner made the decision to go ahead with

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Dr. Phil Zeltzman is a board-certified veterinary surgeon and author. His traveling practice takes him all over Eastern Pennsylvania and Western New Jersey. You can visit his website at, and follow him at

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