How Far Should Cancer Treatment Go?

By Joanne Lynn Intile, DVM, MS, DACVIM on May 15, 2014

A discussion circulated on our veterinary oncology listserv last week about potential further treatment options for a pet with obvious end-stage cancer. The patient previously failed numerous standard of care chemotherapy protocols, as well as a few I would consider “not so standard of care.”

The oncologist posting on the listserv was inquiring about whether any of us had any anecdotal therapeutics we could offer. They acknowledged that although the pet’s disease was extensive and thus far refractory to all previously tried drugs, the animal’s quality of life was considered overall to be good, and as such, they were looking for advice.

As is typical for our listserv, a myriad of responses slowly trickled in. There were the usual, “I’ve had success using xyz chemotherapy,” or, “One time I used xxx drug and had a good response” messages, and I read through with mild interest, until one particular reply caught my interest.

The individual writing their retort essentially offered up the question: “Why do we feel compelled to try and treat these cases in the first place?” Though somewhat abrupt and crass in the wording, I paused to consider their inquiry.

On one hand, we have to consider that without trying novel treatments and without attempting to discover options never previously utilized, medicine would never advance. If we maintain the status quo, we can never expect progress and we will never hope to achieve a cure.

On the other hand, when it comes to animals that cannot voice their wants and needs, medical plans that possess risk of causing morbidity and/or mortality, and owners committing to finance the recommendations we make, how can we in good faith and morals, discuss unconventional treatments?

Some colleagues suggested that not offering additional treatment options for owners is akin to “quitting” or “giving up.” I read those responses with mixed feelings, and surprised myself when I leaned towards feeling angry rather than in agreement with their sentiments.

Am I quitter when I tell an owner “It’s time to stop” when I feel strongly that any further treatment would be not only unlikely to help their pet, but could harm them? Do I give up too easily when a certain plan is not producing the results I anticipated? Am I not working as hard as some other oncologists to try and help my patients? Should I always be looking to push the proverbial bar? And more importantly, why am I not interested in pushing things further and further when my gut tells me the outcome is likely to be poor and/or no different than if we did not pursue a particular plan?

*There are times when I feel that when I was a less experienced doctor, I was more confident in talking with owners about diagnostic and treatment options. I think I truly believed in the “system,” meaning my faith came from textbooks, research studies, and previously established success rates. The more I’ve learned as I’ve practiced my craft, the more I recognize that animals do not care much for research or textbooks, and they tend to ignore the rules of physiology. I’ve also discovered that there can be a distinct point of diminishing returns when it comes to cancer care for pets, which may or may not correspond to their owners' designs and motivations. In such cases, stopping treatment, even if an animal feels absolutely fine, is okay.

Ironically, I struggle with answering the question of how we can truly push the line of progress for veterinary oncology. The most obvious answer lays in our desperate, never ending, and infinite need for well designed, controlled, and randomized clinical trials. Without such information, we are all literally spinning our wheels, spending owners' money, and probably not helping patients in the long run.

But history tells that us some of the greatest pioneers in medicine operated using only their ideas and brainpower, without funding for major research studies. These individuals were typically scorned as heretics and ultimately chastised for their ingenuity.

In fact, when the first multi-drug chemotherapy protocols were initially suggested as treatment options for a variety of childhood cancers back in the 1950s, oncologists were deemed “cruel” and “heartless.” These same protocols revolutionized the treatment of such diseases to the point of actually leading to cures.

Obviously those of us who wish to try different therapies for our patients should not be burned at the stake or tried for our convictions. What we must keep in mind for cases of terminal diseases is our obligation to have a serious and realistic conversation with owners about everyone’s expectations and the potential outcomes.

As a solo oncologist in a busy private practice referral hospital, I’m not in the position to design my own studies or publish my own anecdotes. The limitations I face in making such an impact on my profession are innumerable. I can, however, use my experience and my judgment to assist owners in making decisions about their pets' care, making sure everyone’s goals are achieved, including my own need to feel assured that I am offering reasonable and fair options for my patients.

That doesn’t make me a quitter, but it also doesn't make me a pioneer. It simply makes me the person who will make sure the quality of life for the animals I care for is the most important consideration in any treatment plan I devise.