Pathologist Characteristics Associated With Rendering Higher-Grade Diagnoses for Melanocytic Lesions.
Dermatopathology-trained pathologists were far more likely to render higher-grade melanocytic diagnoses.
Pathologist Characteristics Associated With Rendering Higher-Grade Diagnoses for Melanocytic Lesions.
IMPORTANCE: The incidence of melanoma diagnoses has been increasing in recent decades, and controlled studies have indicated high histopathologic discordance across the intermediate range of melanocytic lesions.
To identify pathologist characteristics associated with tendencies to diagnose melanocytic lesions as higher grade vs lower grade or to diagnose invasive melanoma vs any less severe diagnosis.
DESIGN, SETTING, AND PARTICIPANTS: This exploratory study used data from 2 nationwide studies (the Melanoma Pathology [M-Path] study, conducted from July 2013 to May 2016, and the Reducing Errors in Melanocytic Interpretations [REMI] study, conducted from August 2018 to March 2021) in which participating pathologists who interpreted melanocytic lesions in their clinical practices interpreted study cases in glass slide format.
dermatopathology-trained pathologists were over twice as likely to give higher-grade diagnoses
Nonmitogenic T1a diagnoses (stage T1a melanomas with no mitotic activity) accounted for the observed difference in diagnosis of invasive melanoma; when these lesions, which carry a low risk of metastasis, were grouped with the less severe diagnoses, there was no observed association (OR, 0.95; 95% CI, 0.74-1.23; P = .71).
Among dermatopathologists, those with a higher caseload of melanocytic lesions in their practice were more likely to assign higher-grade diagnoses (OR for trend, 1.27; 95% CI, 1.04-1.56; P = .02).
The findings suggest that specialty training in dermatopathology is associated with a greater tendency to diagnose atypical melanocytic proliferations as T1a melanomas.
These low-risk melanomas constitute a growing proportion of melanomas diagnosed in the US.