Vet checking xray


A diagnosis of cancer in a beloved pet tends to broadside owners like a ton of bricks.

If you do happen to find yourself in this unfortunate position, here are 10 key questions you should ask your veterinarian to help prepare you for the next steps.

1. Are You Sure About the Diagnosis?

The gold standard for diagnosing cancer is a biopsy, but not all cancers can or should be biopsied.

Take, for example, the most common feline brain tumor, meningioma, which has a very characteristic appearance on an MRI. When veterinary neurosurgeons see one, they remove the tumor based on its MRI appearance, without first doing a brain biopsy. 

In this case, the diagnosis of cancer is not 100 percent certain until after the tumor has been removed and the results come back from the pathology laboratory.

2. Does My Pet Need a Biopsy?

Sometimes your veterinarian may suspect a tumor, but a quick diagnostic test, called a cytology, comes back inconclusive.

A feline patient of mine, Charity, developed a lump on her back. The cytology of the lump did not show a malignancy, but since the lump continued to get larger over a couple of months, I suspected a tumor. After sending her to a surgeon, a biopsy of the mass confirmed a fibrosarcoma.

3. Can More Tests Be Performed?

Mast cell tumors, the most common form of skin cancer in dogs, come in three varieties: grade I, II and III. 

Grade II reminds me of a difficult middle child. When I see a mast cell tumor biopsy grade II, I rely on advanced testing of the biopsy to give me additional information about how badly the tumor will behave, further directing my treatment recommendations.

4. What Other Tests Can Evaluate the Extent of the Tumor?

Nearly every dog and cat with cancer needs a chest X-ray to determine if the tumor has spread to the lungs. Based on the typical behavior of your pet’s tumor, an abdominal ultrasound, lymph node aspirate or a CT scan may also be recommended.

5. What Treatments Are Available for This Type of Cancer?

Generally speaking, surgical removal is the most common form of treatment for dog and cat cancer. Chemotherapy and radiation therapy are mainstays as well.

The Veterinary Cancer Society keeps a list of active clinical trials for pets with specific tumors. Keep in mind that treatments being studied in clinical trials may not be available outside the trial, and not all types of treatments work for every cancer.

6. What Are Other Options for My Pet?

When I talk to owners about cancer treatments, I like to give options. Often, more than one combination of treatments is appropriate, and my job is to outline those offerings and their associated prognoses, so the family can decide which option best suits their pet.

7. If My Pet Undergoes Chemotherapy, Will She Be Nauseous?

Face it — pets are tough. Some breeze through treatment without a hiccup, but if there is a problem, we have effective drugs to counteract the chemotherapy drugs.

8. Will My Pet Lose All of Her Fur?

Finally, some good news. The vast majority of cats and nearly all dogs experience very little hair loss with chemotherapy. Even if they do, the hair grows back post-chemotherapy.

9. Should I See a Specialist?

Notice that I didn’t write “Should I see an oncologist?” Input from several different specialists may be required to develop the right plan for your pet’s cancer, including a surgeon, a radiologist, a radiation oncologist and a medical oncologist, like me.

10. What Would You Do If This Were Your Pet?

Pretty much every owner I see asks me this question — and the answer will be different for every family struggling to make the best health care decision for their pet.

I have to admit that my answer to this question is biased. I treat pets with cancer for a living, so I wouldn’t do it if I didn’t always hope that what I have to offer owners will make a pet’s life better, as well as keep the family together a little longer.


Dr. Ann Hohenhaus, a practicing veterinarian for 25 years, is board-certified in both oncology and internal medicine. She maintains her clinical practice at The Animal Medical Center in New York City, providing primary care to her long-term patients and specialty care to pets with cancer and blood disorders.