A Pathologist’s View of Personalized Medicine


Vol. 20 • Issue 12 • Page 48

In college there were two core classes in economics: micro- and macro-econ. A similar, artificial split applies to contemporary healthcare. One is personalized medicine, which corresponds to micro-econ. The other, an analogy to macro-econ, could be termed “societal medicine,” and is related to the rising costs of U.S. healthcare. In truth, both are rapidly evolving in parallel paths and with an intersection only when those paths cross. The coming year is not infinity but could be a watershed year.

Personalized Medicine

There has been-and continues to be-much talk about genomic medicine or molecular medicine, which focuses on the use of, principally, DNA-level information to individualize care for preventive and therapeutic measures.

But let me insert here a few comments about nomenclature. Why is the term molecular restricted to DNA (or RNA), as in molecular pathology? After all, aren’t glucose, troponin and IgG molecules?

In addition, genetic testing nomenclature is confusing.1 Genetic tests should not refer to non-human molecular targets, e.g., infectious agents (HPV, Chlamydia and the like), nor should they refer to tests for acquired mutations such as those found in various cancers, e.g., EGFR in lung cancer, KRAS in colon cancer, etc. As well, the term “genetic tests” should not be applied to tests for patients who have active disease manifestations, e.g., Factor V Leiden thrombophilia. That still leaves a lot of room for genetic tests and, in my opinion, this ought to be the domain of personalized medicine.

Molecular Medicine

One of the most appealing positive views of molecular medicine comes from the Pacific Northwest where Lee Hood has articulated the 4 Ps:

• predictive,

• preventive,

• personalized and

• participatory.2

This is an ambitious vision and the details remain to be fleshed out. It capitalizes on the wealth of information that we now have access to and, with rapidly advancing technology, is within striking distance of affordable. This also is where the excitement lies for molecular diagnostics, i.e., nucleic acid-based testing to identify risk factors so preventive measures may be undertaken and to identify therapeutic targets for which we have pharmacologic agents.

A Matter of Public Policy?

In contrast, Tom Farley, the current New York City Health Commissioner, and Deb Cohen, a senior scientist at the RAND Corporation, published a book, “Prescription for a Healthy Nation: A New Approach to Improving Our Lives by Fixing Our Everyday World,” which argues that relatively small public health measures can lead us to better health. With a focus on obesity, cardiovascular disease and smoking, many of the facets are based on enacting legislation and regulations to create an environment that supports a healthier lifestyle.

Farley and Cohen propose taxing unhealthy foods and/or restricting access of students to fast food establishments (such as limiting placement of such restaurants at a considerable distance from schools). They make a case that this is a more effective approach for societal health than a mechanistic understanding of leptin signaling and using this knowledge for developing (costly) drugs to mitigate those cellular pathways.

In such a discussion a split arises in at least two ways:

• How does one reconcile personalized medicine with public health, which is a part of societal medicine?

• How does one reconcile the cost of personalized medical (health) care with a system that is not capable of absorbing additional costs?

Unanswered Questions

Many uncertainties still exist. There is much talk about the $1,000 genome, a variant of Moore’s Law, within the next couple of years. But there also are many attendant complexities. For example, what is the “gold standard” genome? Who will do the analysis? Can we afford the costs of the drugs for the disease that has been identified?

At the same, in my view, it is the (global) economy that has the most immediate and significant impact. Controlling the spiraling costs of healthcare will require a fundamental change in how healthcare is delivered and is intimately linked to the national economic challenges. It is likely that healthcare organizations, whether ACOs or some other form, will have to figure out how to be profitable at Medicare rates; cost shifting from commercial insurers is no longer an option.

Dr. Cohen is a pathologist, The University of Iowa, Iowa City, and will soon relocate to The University of Utah.

References

1. Rick Press, University of Oregon, personal communication. http://www.slideshare.net/osumedicalcenter/dr-leroy-hood-lecuture-on-p4-medicine

2. Farley T, Cohen DA. Prescription for a Healthy Nation: A New Approach to Improving Our Lives by Fixing Our Everyday World. Boston, MA: Beacon Press, 2006.

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