Diagnostic Challenges in Dysplastic Nevi: A Retrospective Case Series With Histopathological Reassessment and Immunohistochemistry

Background: Dysplastic nevi remain diagnostically challenging because of their histopathological overlap with early melanoma.Objective: This study aimed to evaluate the challenges in differentiating dysplastic nevi from melanoma, emphasizing histopathological reassessment and the complementary role of immunohistochemistry.Methods: This retrospective case series included 31 melanocytic lesions initially diagnosed as atypical melanocytic proliferations between 2022 and 2023.Clinical, histological, and immunohistochemical data were reviewed, and cases were reassessed by an experienced dermatopathologist.Results: Diagnostic discrepancies were identified, particularly among lesions with high-grade atypia.Ki-67 and other available immunohistochemical findings provided complementary information in diagnostically challenging lesions.Overall, 16 of 31 lesions (51.6%) were reclassified as melanoma; among the 26 lesions initially diagnosed as dysplastic nevi, 16 (61.5%)were reclassified as melanoma.Conclusion: These findings highlight the diagnostic complexity of dysplastic nevi and support expert dermatopathological review, careful clinicopathological correlation, and the integration of immunohistochemistry in borderline melanocytic lesions.This integrated approach may help reduce diagnostic misclassification and support appropriate clinical management.