A nongrading histologic approach to Clark (dysplastic) nevi: A potential to decrease the excision rate

作者：Lozeau Daniel F; Farber Michele J; Lee Jason B^*

来源：Journal of the American Academy of Dermatology, 2016, 74(1): 68-74.

DOI：10.1016/j.jaad.2015.09.030

• atypia
• biopsy
• Clark nevus
• diagnostic uncertainty
• dysplastic nevus
• excision
• melanoma

Background: Despite a lack of evidence that dysplastic nevi are precursors to melanoma, a large proportion of dermatologists continue to treat them as such. Emerging data suggest that histologic grading approach may result in many unnecessary excisions.
Objective: Using a nongrading approach to diagnosis of Clark/dysplastic nevi, the current study sought to define and determine the diagnostic uncertainty rate, and to report on the results of re-excisions of such lesions.
Methods: All melanocytic nevi submitted to an academic dermatopathology laboratory between January 1, 2007, and December 31, 2013, were categorized. The number of Clark nevi recommended for re-excision divided by the total number of Clark nevi was taken to be the diagnostic uncertainty rate.
Results: This nongrading approach resulted in an excision recommendation/diagnostic uncertainty rate of 11.1%. In 2% of the excised specimens, the diagnosis was changed to melanoma. Limitations: The study was performed at a single institution, and assigned diagnoses could not be verified other than by the diagnosing dermatopathologists. Lesions that were not submitted as re-excision specimens could have altered the results had they been available for evaluation.
Conclusion: Compared with previously reported excision rates, the current study shows that the nongrading approach to Clark nevi results in a lower excision rate while still maintaining a low rate of change in diagnosis similar to the grading approach.

• 出版日期2016-1