Benign melanocytic lesions mimicking melanomas.
Review of problematic melanocytic consultation cases has enabled identification of the most common variants of benign melanocytic proliferations which can be confused with melanoma. Apart from Spitz naevus, the most common in this group of lesions are pigmented spindle cell naevus and atypical dermal nodule. Potentially the most problematic but less common are pseudomelanoma following incomplete removal of a naevus and 'activated' benign naevus cells in sentinel lymph nodes. By considering the overall architecture and the degree of nuclear atypia of the lesions, all of these problems can usually be resolved. Nuclear or architectural abnormalities by themselves are insufficient and must be assessed together. In addition, the combinations of pattern and cytological change in most of the lesions described here are distinctive and have become recognised as known variations of benign entities.
Cook
Martin G
MG
Department of Histopathology, Royal Surrey County Hospital, Postgraduate Medical School University of Surrey, Guildford, UK. mgcook@globalnet.co.uk
D003937:Diagnosis, Differential; D006801:Humans; D009508:Nevus, Pigmented / Q000473:pathology*; D011230:Precancerous Conditions / Q000473:pathology*; D012878:Skin Neoplasms / Q000473:pathology*