Understanding and Practice:

Understanding and Practice:

How deeply do I understand the bases for my medical decisions? What constitutes practical understanding?

I practice a high stakes type of medicine: hematology and oncology.  My patients have life threatening diseases.   Patients expect a highly educated, highly informed opinion about how to proceed.  They believe  that I understand the medical research  that forms the basis of the treatment plans.  What does it mean: "to understand"?

Understand is a word that consists of two components:  under and stand, both easily  comprehended English words. I can imagine this combination  of words to mean having a relationship with the subject that  does  not crush me, I can stand under the image and look at it objectively and agree.  I can bring supporting ideas to bear on the issue, see the basis of the conclusion. 

To understand disease and treatment  has a variety of its own  meanings.  There is a  quantitative aspect to understanding, it can be broad or narrow, superficial or deep. Using these terms to describe understanding reflects its architectural nature.  Understanding is a structure.  If it claims to be  tall its foundation must be very deep, it can easily topple,  a  poorly supported claim of understanding is a very insecure structure.

Within medicine, within oncology, understanding means different things. Evaluating microscopic images requires a set of cognitive skills that is quite different from evaluating the statistics of clinical trials outcome data.  The  interpretation of large data sets that describe  outcomes is  very separate from that molecular biology that describes the mechanisms of disease and recovery. Once  a particular type of interpretation is relegated to an expert, without review by the deciding physician, it become religious scientism, faith in a vaguely understood process, believed on the basis of a report there is an unrecognized underpinning of pure faith.   It is the intelligent  integration of the various facets of information that constitutes understanding.  Understanding requires skepticism and self criticism.

The practice of medicine requires sufficient understanding to know when to use a given therapy and when  not to.  It implies a knowledge of how to administer the treatment and how to deal with its consequences.  Unfortunately, in our rapidly changing world, depth has become optional.

Often, the understanding is quite superficial.  It consists of  recognizing a  pattern that identifies a disease, reviewing sets of  guidelines or  published recommendations;  deciding  among the various alternatives; beginning   treatment; and dealing with consequences.  This pattern of behavior  is not simple and requires a high degree of education and intelligence.  But it  is not what I call understanding. 

In our era,we have come to question the  value of deeper understanding . The big data approach suggest that the  analysis of a large enough data set  will yield a better set of predictions  than a model  of disease and treatment based,  theoretical "understanding" of (an imagined)  underlying mechanism. There is undoubtedly a role for this kind of agnostic knowledge.  But, an approach that denies any level of mechanistic  understanding may fail to   identify  the heterogeneity of the data set and  obscure important information. In the large dataset we are often naming a number of diverse  entities the same diagnosis.  We now recognize some of these differences and separate the abnormalities that will reliably respond to  their special treatments, but this process of differentiating molecular diagnoses is in its infancy.  It is only begining to penetrate clinical trials.

 What we currently call a diagnosis usually does not correspond to a single molecular entity.  A  diagnosis  today is  a combination of a clinical history, physical and radilogic findings, a particular microscopic appearance with certain stains,  an aberrant  collection of  surface molecules, and/or a  set of mutations  in critical genes. Whe the diagnostic lable is attached , there is often no recognition of the methods used to arrive at the diagnosis. Sometimes one set of methods is applied, sometimes another

The important,  practical goal  is the  identification of a  distinguishing mark that directs therapy, the piece of information that will lead to cure.   Finding that is something I can support.  When I have that piece of information, in a practical sense,  I understand.