What Is Our Best Defense On Biopsy Timing For Potential Melanomas?

Bryan Markinson DPM FASPD


My position is that the converse is not true. Specifically, it is not always certain that a time delay in diagnosing melanoma will adversely affect long-term survival. For the purpose of this blog, let us define “early” as when the tumor is confined to the epidermis and theoretically does not have the ability to disseminate.

Everyone, doctor or not (even jurors), intuitively accepts that the longer a malignancy is hanging around, the worse the prognosis. It is very easy to make this statement and extremely hard to refute.

However, the science does not reveal this conclusively in any way. In the case of melanoma, there are lesions that may remain in the radial or horizontal growth phase for as long as five to 20 years.1 Lentigo maligna melanoma, which commonly occurs on the face, is known for this. Melanomas also do not grow at a uniform rate. They may be slow growing initially and then start to grow rapidly all of a sudden at unpredictable times. They may start out with rapid growth and slow down. Undoubtedly, some melanomas become invasive very rapidly as is thought to be the case with nail unit lesions, particularly the amelanotic nodular variant common in nail beds.

What science does reveal conclusively is that the best indicator of prognosis is the stage of the lesion at the time of diagnosis, not how long the lesion has been there.2 It is mere conjecture that the single parameter of long duration of the lesion indicates a worse prognosis.

Therefore, when faced with allegations of delayed diagnosis, the defense becomes easier, but not easy, if the chart documents the presence of the lesion and a short statement as to why you are or are not doing a biopsy. This should be supported by documentation of the presence or absence of established ABCDE criteria (asymmetry, border irregularity, color variegation, diameter greater than 6 mm, enlargement or elevation). Measurement of the lesion is critical and photography can be enormously helpful.

However, at some later stage, it is not hard to find an expert to say that if one diagnosed the patient at the time one saw the lesion, the prognosis would be better. Can anyone, including the patient, ever be certain when the lesion surfaced? Is it ever possible to know when day one occurs?

It takes great skill for an expert witness to convince a jury of laypeople that day one may actually be long before the clinician ever saw the lesion. However, it is almost impossible to remove from the patient’s and jurors’ minds that day one occurred when the patient walked into your office.

Due to this difficulty, even with a very strong defense position, settlement may be the best outcome we could achieve. I therefore opine that we are best off if we document that we performed a biopsy at the “earliest” possible moment, based on appropriate diagnostic criteria and not necessarily at an “early” stage of tumor growth. This in my view is our best defense but hardly a slam dunk when it comes to a jury.


1. Swetter SM, Geller AC, Kirkwood JM. Melanoma in the older person. Oncology 2004 Aug; 18(9):1187-96; discussion 1196-7. Available at http://www.psychiatrictimes.com/display/article/10165/104948

2. Bennett DR, Wasson D, MacArthur JD, McMillen MA. The effect of misdiagnosis and delay in on clinical outcome in melanomas of the foot. J Am Coll Surg 1994 Sep; 179(3):279-84.


The two melanomas I have treated were both plantar lesions that presented as granulomas in appearance. There was never a mole there previously. They were both level 4 when biopsied. I don't know for sure but I believe that once this type of lesion is visible, it is already late-stage with a poor prognosis vs. some of the more typical types encountered.

Yours truly,
Robert Rubin D.P.M.

Never a mole there previously? Are you certain of this? The important thing is that you performed a biopsy at initial presentation. Having done so, you have completely eliminated the risk of delayed diagnosis allegations against you. It is true that amelanotic lesions are typically nodular on the foot and it is generally believed that these do grow vertically rapidly. However, this is not a certainty and as such, I would not agree in lock-step with your statement "once this type of lesion is visible, it is already late-stage with a poor prognosis."

Thanks for your comment,

Bryan C. Markinson, DPM

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