On “precision” and “personalized” medicine …

“Personalized medicine” and “precision medicine” have become two of the medical “buzz-terms” of the 21st Century. However, they aren’t the same thing at all.

In all truth, “personalized medicine” has been with us since Hippocrates and earlier. Here’s why.

Every surgical procedure ever carried out is a form of personalized medicine, and every half-decent surgeon knows it. Even when one specializes in the conduct of a very specific type of surgical procedure, there are going to be small — and sometimes critical — differences each time one does that procedure, because every patient’s anatomy and biology is slightly different.

To quote Arnon Krongrad, the surgeon who first started to carry out laparoscopic radical prostatectomies on a regular basis here in America, back in the late 1990s, well before the availability of the Intuitive robotic system:

… all really good surgeons are on their learning curve forever. My surgeon will be insightful and open enough to concede that there is no end to learning. (S)he will be humble enough to stay 120% focused and alert throughout every surgical procedure. As a surgeon myself, I know that if I ever start to think I’ve seen it all, the next patient will walk in the door to prove me wrong.

Krongrad, A. How to pick a prostate cancer surgeon.
The “New” Prostate Cancer InfoLink.

Every heart transplant carried out, to give a now common example, is personalized to the individual heart recipient in numerous different ways — including the precise type of therapy that must be administered long-term to prevent rejection of the transplanted heart.

The same can be said, with the same types of patient-specific individuality as the key driver, with respect to every type of radiotherapeutic procedure and every type of cognitive-behavioral, interpersonal “talk therapy” ever carried out. Individual patient factors have to be addressed with enormous care if a high-quality outcome is to be expected and achieved.

We also now have truly personalized forms of biopharmaceutical therapy, with drugs that are custom-created from the patients’ own cells to treat very specific conditions: the use of sipileucel-T (Provenge) in the treatment of advanced prostate cancer was the first such intervention to be approved by the U.S. Food and Drug Administration. Most of the current types of CAR T cell therapy approved and in development use the same type of process. The treatment for each individual patient is created by extraction of sufficient T cells from the patient in question; a chimeric antigen receptor (CAR) is added to the patient’s T cells; and the new, personalized CAR T cells are then re-infused back into the patient.

“Precision medicine” is closely linked to the premise of “personalized medicine”, but it is not the same thing.

At the time of it’s launch in 2015, the Precision Medicine Initiative provided the following definition of “precision medicine”:

… an innovative approach that takes into account individual differences in people’s genes, environments, and lifestyles. It gives medical professionals the resources they need to target the specific treatments of the illnesses we encounter, further develops our scientific and medical research, and keeps our families healthier.

Thus, precision medicine is a long-term strategy to make truly personalized medicine possible in ways that will increase the probability that individual patients will be able to get diagnosed and treated accurately, effectively, and safely based on all of their individually different information about themselves and their evident disorder.

One of the problems is that a lot of people tend to use the two terms interchangeably. That’s an error. They are not interchangeable. To get a clear grasp of the difference, try this article on the Healthcare IT Analytics web site, which initially states that precision medicine is “commonly referred to as personalized medicine” and then explains in detail why they are two very different animals … even though that wasn’t the initial intent of the article.

What is 100% true is that the better we can get at precision medicine, the more it will become possible to provide accurate, effective, and safe personalized medicine to an individual patient.

If there is something that is arguably being “over-hyped,” it is the degree of effectiveness and safety certain types of “personalized” high-tech care currently available. To pick on the new forms of immunological therapy such as CAR T in the treatment of some types of cancer, we have seen truly astonishing results in small numbers of patients, and we will continue to see such astonishing results, but it may be a long time before we see a high level of efficacy of this type of care in a large percentage of the patients who are so treated. When it comes to this type of medical care, we are only at the beginnings of the learning curve. There is still a very long way to go.

And then there are the gene therapies that are specific to individuals who have very specific forms of inherited or somatic genetic abnormality. Strictly speaking, to date, these are not really “personalized” forms of medical care because they can be applied to a spectrum of patients who have a well-defined genetic abnormality. But often these therapies only work really well for small numbers of patients with such rare disorders, and so, for these patients and their families, when they work well, they certainly feel like personalized medicine. Again, however, there can be considerable variation in how well these types of care actually work across the spectrum of patients who meet the key criteria for treatment. On the other hand, all gene therapy is quite certainly a form of “precision medicine”. We are treating a specific set of patients who have a known, treatable, genetic abnormality with a form of care that can reverse the consequences of that genetic abnormality. But our genes aren’t the same thing as our bodies, and so some patients will do very well indeed with certain types of gene therapy and others with the same genetic abnormality may not.

It’s complicated … but what can be argued with absolute certainty is that over the next 80 years we are going to make great strides toward the goal of truly “personalized” medicine as we apply all the learnings from the academic and practical pursuit of “precision” medicine.

Pick your words with care!

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.