What Know and What We Think

ROBERT McNUTT, MD

What matters is what we know, not what we think

In the late 1980’s I cared for a pregnant woman with breast cancer. Breast cancer is the most common cancer in pregnancy, but uncommon in number, occurring in about 1 in 3000 pregnancies. It is a compounded emotional treating experience for sure, and at that time uncertainty in how to treat was the norm. The woman had a mastectomy but did not take chemotherapy based on concern for her baby.

Three months after her delivery, now getting chemotherapy for her aggressive breast cancer, the woman asked me to consider treating her newborn child with “mild” chemotherapy, a clear contrarian idea given her reluctance to expose her child while in her uterus. Her reasoning, she said, after giving it “lots” of thought, was that it made sense to her; she had cancer at a young age and reasoned her child would also. In her mind it was rational and reasonable to give her child treatment.

Fear and depression fueled her concern, for sure, and universally we would deny the request. The woman would not live to see her child’s second birthday and wanted to do what she could for her. But, there was no evidence of benefit to the baby, making her request irrational. So, I did not comply. In fact, what would you have thought of me if I had complied with this woman’s concerns?

In 1882 a surgeon reasoned that removing a woman’s cancerous breast, nodes, and muscles was the way to get rid of breast cancer. There was no proof of benefit, but the idea spurred action. That idea, and the radical surgery, persisted even after the publication of a randomized trial (NSAPB-04) in 1974 showing that more surgery was not better than less; yet, about 5000 radical mastectomies were still performed in 1983, about 100 years after the first. What should we think of physicians who acted without proof of benefit, and, even, after proof of no benefit?

In the 1990’s over 40,000 women had high-dose chemotherapy and bone marrow transplant if they had breast cancer. Some of those women died of treatment; I know so because I knew some. The intervening years between the ideas of doing more and more to a woman with breast cancer and the publication of randomized trials showing that more and more was actually less was marred by politics and legal threats for not performing the “best”, and most. All this wrangling occurred without knowing if the treatment plan was better than others. What should we think of those physicians, lawyers, and insurers who forced compliance and then complied with an idea rather than knowing what was best?

In a previous blog, I showed data on bilateral mastectomy for DCIS; there is data, but no information, as comparative studies have not been done [link]. I was consulted by several women who were considering complying with the bilateral procedure based on ideas that getting rid of everything might be good for them. Their physicians had proposed the procedure. What should we think of these physicians for proposing an unproven procedure based on an idea?

Acting without knowing, in my view, should be considered an abdication of professional responsibility. A professional obligation includes informing patients that there is no evidence of benefit for some treatment plans, and then not proposing the plan.

The only way a decision can/should occur is if there is a balance between compared options. The compared options must be examined in studies that give the best chance of determining the independent contribution of one intervention versus another (randomized). The balance that emanates from these studies is that some treatment will be shown to independently contribute to better disease related outcomes at the expense of more treatment related complications. The differences in outcomes of disease and treatment compete for a patient’s attention, and choice.

Without such comparisons, no choice should be made. Ideas don’t suffice; it doesn’t matter whether the ideas are the physician’s or the patient’s.

How many 100, 000’s of women underwent radical mastectomy before it took only 1700 in a randomized trial to show it offered no benefit despite increased harm? What about high dose chemotherapy and bone marrow transplant? Six randomized trials, reviewed in 2005, including only a cumulative total of 850 women, showed high-dose treatment offered nothing, but studies kept trying to prove the value until finally 14 randomized trials, now including 5600 women came to the same conclusion. Far more women got the procedures before knowing what was best than the number required to find out what is best in the first place. This should be a lesson to us all. Knowing is better than not knowing, and doing without knowing may be the worst thing a profession can do.

I am writing this blog with a purpose. That purpose is to make physicians and patients uncomfortable about acting on beliefs without evidence from comparative research trials. I believe patients are the best decision makers, but that will be shown to be true only if they are informed and allowed to decide.

But, physicians need to be on board, as well. They should not allow treatments of unproven benefit and, instead, they should demand study over action. There are too many examples of the failure of “good ideas” to subsequently help patients. What matters is what we know, not what we think. Informing patients that no evidence exists, and promoting a dutiful process of scientific inquiry could be a powerful way to change medical care for the better.

from THCB http://ift.tt/2ziiod8