A 1 cm pigmented lesion was noted on the back of an 83 yo man during his annual visit to his primary care provider. The lesion had a play of color and irregular borders Two representative areas were sampled with 3 mm punch biopsies.
Dermatoscopic Image
Pathology: This is a compound melanocytic proliferation showing moderate melanocytic atypia. Diagnosis: Moderately Atypical Compound Melanocytic Nevus extending to the margins.
After seeing the dermatoscopic image, the pathologist ordered a PRAME. This showed a weak positivity throughout the lesion. For more on PRAME.
Discussion: This will be excised with 5 mm margins. Reference 1 is a good overview of late onset atypical melanocytic nevi.
Based on dermoscopy, Melanoma-In-Situ needs to be considered. Reference 2
References
1. Utilizing PRAME Expression and a Meta-Analytic Framework for iSALT to Explore Atypical Late-Onset Nevi of the Elderly and Their Relationship With Lentiginous and Nested Nevoid Melanomas Am J Dermatopath 2024 Dec 1;46(12):825-832. Steven Kossard, Shahin Sharifi, Linda Calvey Full Text: PMC
2. Rajan Ramji, Guillermo Valdes-Gonzalez, Amanda Oakley, Marius Rademaker. Dermoscopic 'Chaos and Clues' in the diagnosis of melanoma in situ. ustralas J Dermatol 2018 Aug;59(3):201-205. doi: 10.1111/ajd.12740.
Using pattern analysis, 82% of the lesions had three or more patterns
(multicomponent). Colours includedlight brown (100%), dark brown (98%)
and grey (75%). All MIS demonstrated chaos. The most prevalent clues
were thick lines (88%), eccentric struc-
tureless areas (88%), and grey or blue structures (75%).
Dermoscopy can be very helpful in the early diagnosis of melanoma and
MIS. The Chaos and Clues method is simple to use. Its unambiguous
descriptors can be successfully used to describe MIS. The presence of
chaos and clues to malignancy (including thick lines, eccentric
structureless areas, and blue/grey structures) should raise a red flag
and lead to referral or excision.
