Manuel Valdebran1, Justin Bandino2, Amira Elbendary3, Abdallah Gad4,5, Krishna C Arudra6, Sébastien de Feraudy1, Dirk M Elston7. 1. Department of Dermatology, University of California, Irvine, California. 2. Department of Dermatology, San Antonio Military Medical Center, San Antonio, Texas. 3. Dermatology Department, Kasralainy Faculty of Medicine, Cairo University, Egypt. 4. Department of Biostatistics and Cancer Epidemiology, National Cancer Institute, Cairo University, Cairo, Egypt. 5. Department of Internal Medicine, Texas Tech University Health Sciences Center, Odessa, Texas. 6. Dermatopathology Service, MD Anderson Cancer Center, Houston, Texas. 7. Department of Dermatology and Dermatologic Surgery, Medical University of South Carolina, Charleston, South Carolina.
Abstract
BACKGROUND: Interpretation of Clark's nevi has generated debate over the years; although criteria have been proposed for grading morphological features of melanocytes, there is still confusion and variability in the assessment of these lesions. METHODS: This is a retrospective observational study conducted on 100 Clark's nevi and 84 melanomas. A single expert dermatopathologist evaluated all blinded and randomized photomicrographs of both the Clark's nevi and melanomas for the presence of 14 cytologic features. Subsequently, a multivariate model was used to obtain sensitivity and specificity. RESULTS: Clark's nevi showed a significantly higher frequency of absent-or-inconspicuous nucleoli over melanoma, whereas mitotic figures, pleomorphism, notching, multiple nucleoli, peppered moth nuclear pattern, flattened adjacent nuclei, prominent nucleoli and vesicular nucleus with rounded nucleoli were found significantly higher in frequency in melanomas. CONCLUSION: Our data suggest that nuclear alterations are of value in the differentiation of atypical nevi from melanoma.
BACKGROUND: Interpretation of Clark's nevi has generated debate over the years; although criteria have been proposed for grading morphological features of melanocytes, there is still confusion and variability in the assessment of these lesions. METHODS: This is a retrospective observational study conducted on 100 Clark's nevi and 84 melanomas. A single expert dermatopathologist evaluated all blinded and randomized photomicrographs of both the Clark's nevi and melanomas for the presence of 14 cytologic features. Subsequently, a multivariate model was used to obtain sensitivity and specificity. RESULTS: Clark's nevi showed a significantly higher frequency of absent-or-inconspicuous nucleoli over melanoma, whereas mitotic figures, pleomorphism, notching, multiple nucleoli, peppered moth nuclear pattern, flattened adjacent nuclei, prominent nucleoli and vesicular nucleus with rounded nucleoli were found significantly higher in frequency in melanomas. CONCLUSION: Our data suggest that nuclear alterations are of value in the differentiation of atypical nevi from melanoma.