Case 1 Female, 24 years. Pigmented lesion, skin of wristShow diagnosis & comments
Small focus of melanoma within Spitz naevus
Spitz naevus has a reputation of never progressing to melanoma. However, this is difficult to prove. The vast majority of naevus remnants that are encountered is association with melanomas are of the usual (compound or intradermal naevus NOS) type. However, a remnant of Spitz naevus is more difficult to recognize next to a melanoma, since a Spitz naevus remnant would show large (Spitz) cells that are more difficult to distinguish from melanoma than the usual small naevus cells are.
This lesion shows a Spitz naevus with a small focus of highly atypical dusty pigment-laden melanocytes, with architectural irregularity, that is indicative of melanoma. Thus, I think this is one example of a very small melanoma localized within, and probably arising from, Spitz naevus.