Melanocytic lesions are common in routine surgical pathology. Although the majority of these lesions can be confidently diagnosed using well-established morphologic criteria, there is a significant subset of lesions that can be diagnostically difficult. These can be a source of anxiety for patients, clinicians, and pathologists, and the potential consequences of a missed diagnosis of melanoma are serious.
To provide a practical approach to the diagnosis of melanocytic lesions, including classic problem areas as well as suggestions for common challenges and appropriate incorporation of ancillary molecular techniques.
Literature search using PubMed and Google Scholar, incorporating numerous search terms relevant to the particular section, combined with contemporaneous texts and lessons from personal experience.
Although a subset of melanocytic lesions can be diagnostically challenging, the combination of a methodical approach to histologic assessment, knowledge of potential diagnostic pitfalls, opinions from trusted colleagues, and judicious use of ancillary techniques can help the pathologist navigate this difficult area.