| Autor: |
Zboraș I; Department of Dermatology, 'Iuliu Hațieganu' University of Medicine and Pharmacy, 400006 Cluj-Napoca, Romania., Ungureanu L; Department of Dermatology, 'Iuliu Hațieganu' University of Medicine and Pharmacy, 400006 Cluj-Napoca, Romania., Șenilă S; Department of Dermatology, 'Iuliu Hațieganu' University of Medicine and Pharmacy, 400006 Cluj-Napoca, Romania., Petrushev B; Department of Pathology, Regional Institute of Gastroenterology and Hepatology, 400162 Cluj-Napoca, Romania., Zamfir P; Department of Pathology, Regional Institute of Gastroenterology and Hepatology, 400162 Cluj-Napoca, Romania., Crișan D; Department of Pathology, 'Iuliu Hațieganu' University of Medicine and Pharmacy, 400006 Cluj-Napoca, Romania., Zaharie FA; Faculty of Medicine, 'Iuliu Hațieganu' University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania., Vesa ȘC; Department of Pharmacology, Toxicology and Clinical Pharmacology, 'Iuliu Hațieganu' University of Medicine and Pharmacy, 400337 Cluj-Napoca, Romania., Cosgarea R; Department of Dermatology, 'Iuliu Hațieganu' University of Medicine and Pharmacy, 400006 Cluj-Napoca, Romania. |
| Abstrakt: |
PRAME (PReferentially expressed Antigen in Melanoma) immunohistochemistry has proven helpful in distinguishing malignant from benign melanocytic tumors. We studied PRAME IHC expression in 46 thin melanomas and 39 melanocytic nevi, mostly dysplastic nevi. Twenty-six percent (26.09%) of the melanomas showed diffuse PRAME staining in over 76% of the tumor cells (4+), and 34.78% of the melanomas showed PRAME expression in over 51% of the tumor cells (3+ or 4+), while 8% were entirely negative for PRAME. No melanocytic nevi were PRAME 4+ or 3+. More than half of the nevi (64%) were entirely negative for PRAME staining, and 36% of the nevi showed staining expression in 1-25% (1+) or 26-50% of the cells (2+). No nevi were stained with a color intensity of 3, while 16.67% of the melanomas were stained with this color intensity. Most nevi (78.57%) were stained with an intensity of 1. With a lower positivity threshold, sensitivity increases with still reasonable specificity. The best accuracy was obtained for the 2+ positivity threshold. In conclusion, PRAME staining helps distinguish thin melanomas from dysplastic nevi. However, the threshold of positivity should be lowered in order not to miss thin melanomas. |
