Risk vs. Reward When Doing Biopsies

We are all familiar with the phrase “risk vs. reward”.  It’s used a lot in financial transactions.  If I take this risk…what will be the reward that I receive? It’s a great way of looking at nearly everything, to determine if the benefit you may receive IS worth the risk that you take.

In medicine, it’s no different when you are looking at diagnosing or treating a patient.  Is the risk of taking this medication worth the benefit that the patient will receive?  And it’s also true about diagnostic procedures.  Even a simple blood draw has the risk of hematoma and infection, but typically that risk is minimal compared to the benefit that you gain by obtaining great insight into the patient’s health through the results of the laboratory testing.

But not every test is that simple.  For example, the process of taking a punch biopsy from a lesion on a patient is a risk to the patient.  Infection.  Chronic wound.  Scar. Pain.  These are all items that can result from a punch biopsy; not all do, but they can occur.  And often the results from a punch biopsy IS worth the risks for these complications when you find out that the patient does or does not have a malignancy.  Or a specific type of dermatitis or other diseases.

But what about when an invasive test, such as a punch biopsy, is done when there are other non-invasive methods of evaluating the patient, with perhaps equal or better data?  In that case, is it worth the risk to the patient to do an invasive test when something safer and simpler would suffice? Probably not. You have to think about what would be the impact of a side effect on the patient.  Infection?  Non-healing wound?  How would you be able to justify it in a court of law if it came to that?  How would you answer a question about other less-invasive alternatives?  Or your indications of why you did the biopsy.


One such test that may fall under this category is the “Trans-Epidermal Nerve Fiber Density” which is a complex test, (i.e. generates multiple CPT codes for the laboratory) and may be of limited utility.  Why do I say this?  Let’s see….

Which of these two scenarios gives you a better idea of the patient response to your treatment?

  • A patient’s detected sensation to a pin prick examination has extended 5 cm more distal to the patella than it was several months earlier.
  • A patient’s TENFD at the ankle has improved from “just outside the normal range” to “just inside the normal range” over a period of several months.

Now you may think that the TENFD test is more “scientific” than a pin prick test, but does it really tell you about the functional improvement that the patient has experienced, as the pin prick test does? And, you may not be aware of the significant biologic variation and test variation that can impact the numbers in a TENFD test.  Just like a glucose test, AST, or uric acid tests, the TENFD test is subject to what is called “CV”, which is the variation that you can see from run to run, where you get different numbers even when testing the exact same specimen!  For glucose…a 5% CV means that a level of 95mg/dL and 105 mg/dL are really the “same” answer because both are within the 5% CV difference from the true value of 100 mg/dL!   There is no difference in doing TENFD, except that the CV may be substantially higher.  Variations such as biopsy location; time to fixation; time to staining; staining variation; cutting variation; counting variation all play into the overall variation that you can see in the TENFD testing.  What may seem to be an exacting test may be less than you think.

Now for the second issue…

WHY are you doing the test on a patient?  Typically it’s because of their impaired sensory nerve function in their feet.  And what it the most typical cause of that?  Diabetes.  And what else occurs in diabetic legs and feet?  Vascular disease.  So WHY would you intentionally put a biopsy hole in a diabetic’s leg or foot, which puts them at substantially higher risk of infection and complications than leaving the site intact, when you can get nearly the same functional information from a non-invasive test?  Why?

If you are not prepared to answer that…then you should probably think twice before doing such biopsies.  It’s not a question of IF a complication will happen, it’s a question of WHEN it will happen. And when it does, you will be the one who has to answer to the patient…or their “representative”.

Our Philosophy

At 4path, we want business as much as any other laboratory, but we also look beyond that simple self-serving focus. We look at the patient and ask with each test that we offer…Does this really provide a benefit to the patient?  Is it worth the risk to the patient?  Is it worth the cost to the patient?

This philosophy is true when we are asked about the use of TENFD testing for patients. Yes, it could be “financially good” for our business (there are several CPT codes associated with this testing), but it probably doesn’t provide the doctor with really meaningful information beyond what can be obtained by a good physical examination of other forms of non-invasive testing.   This approach is also true in our approach to diagnostically effective yet financially responsible testing for nail fungus.  And it’s true for other tests that we perform.  We don’t like putting patients at risk for testing with limited utility. We don’t like generating bills to patients for testing that is unnecessary or redundant. We look out for the good of your, and our patients, first and foremost.

Give us a call (877-884-7284) and let us provide diagnostically effective and financially responsible anatomic services to your (and our) patients. It’s what they deserve..and what you deserve.


Image credits:  Wound:  Chrst Campbell  Exam:NYU.edu

By | 2017-02-01T18:39:31+00:00 February 1st, 2017|Uncategorized|Comments Off on Risk vs. Reward When Doing Biopsies