By Evan Falchuk

The Wall Street Journal’s Health Blog says that cancer lab tests “aren’t always right.”

They report on reports issued by two professional societies that point out that as many as 20% of a certain kind of test are inaccurate.  According to the Health Blog the problem is the tests “aren’t black and white, and rely on a pathologist’s judgment.”

Now, judgment is a critical factor in most everything in medicine, but perhaps nowhere else are the consequences of incorrect judgment so serious as in pathology.  As Dr. William Osler famously observed: “As is your pathology, so goes your clinical practice.”

But how widespread is this problem?

Published studies show that as many as 50% of pathology errors are due to “misinterpretation.“  Countries outside of the U.S. have been quicker to recognize to this problem, with the British and Canadian authorities trying to deal with major scandals resulting from the terrible harm that can come to patients from these kinds of misinterpretations.

We see these kinds of problems in our work at Best Doctors, too.

In cancer cases, we have learned that it is critical to have pathology re-reviewed at a major teaching hospital in order to make sure that the initial read was correct.  In our data from thousands of U.S. cases over the last 24 months, covering a very wide variety of cancer, we found that 15% of diagnosed cancers had misinterpretations in their pathology results.  In many cases, the correct interpretation led to major changes in the patient’s treatment plan.  These results track closely with the results of published studies on the problem.

Your life may depend on the judgment, and experience, of the pathologist.  If a pathologist has seen your kind of disease 1,000 times, he or she is going to be much more likely to interpret your sample correctly than one who has one seen it only a few times.  The trouble is, you likely have no idea who your pathologist is, what kind of experience they have, how long of a day they had had by the time they got to your sample, or likely anything else about what they did or who they are.

Ask questions.  Don’t be afraid to ask for a second opinion in which your pathology is going to be re-reviewed by someone else.  Your pathologist’s judgment is probably excellent, but if it’s not the consequences can be severe.  Be sure you are completely comfortable with what you’re being told before you do anything.