Dr. Whitney High reviews some highlights from his lecture " Pigmented Lesion Pearls From the Experts" on Thursday, November 7, 2024, at the 5th Annual Elevate-Derm West Conference at the Westin Kierland Resort in Scottsdale, Arizona.
In this video
Dr. High describes his combined dermatology and dermatopathology practice as "a wonderful combination" that lets him see the lesion both under the microscope and on the patient in front of him. He warns that partial capture of pigmented lesions is "fraught with danger," showing cases where melanoma occupied only one area of a broader lesion — and noting that a 4mm punch may sample only about 1/500 of the specimen by volume. Because of this sampling error, he argues it is sometimes more appropriate to choose a technique that samples all or substantially all of the pigmented process rather than a shallow shave or punch.
On the microscope side, he stresses that reading pigmented lesions carries real subjectivity: a series of judgment calls starting with the silhouette and cell morphology, sometimes aided by immunostains like p16 (loss associated with melanoma) or PRAME (nuclear expression concerning for melanoma). None of these are "thumbs up, thumbs down" — a final subjective call still rests with the dermatopathologist. He calls amelanotic and nevoid melanoma "everybody's nightmare," best suspected on history — a new, changing, rapidly growing, ulcerated, bleeding or painful lesion. And he reminds practitioners that gene expression profiling tests, while valuable, are built on statistics that can be right for a population yet wrong in a single case, so results should be framed as what the studies show, not a guarantee.
