basal melanocyte proliferation
Thursday 29 November 2012
Lesions with basal melanocyte proliferation
Lesions with basal melanocyte proliferation are characterized by basal hyperpigmentation and an increase in melanocytes in the basal layer.
The melanocytes are usually single and cytologically normal. Small junctional nests are sometimes seen.
Epidermal acanthosis and the presence of melanophages in the papillary dermis are additional histological features that are usually seen in entities within this group.
In addition to the lesions discussed below, melanocytic hyperplasia can occur in lichen simplex chronicus, in the skin of the eyelid of elderly patients, and in sun-damaged skin.
The proliferation of melanocytes in skin exposed to the sun is sometimes mildly atypical and this may pose difficulties when it is present near the edge of an excision specimen.
- lentigo simplex
- solar lentigo (senile lentigo)
- lentiginous nevus
- speckled lentiginous nevus (spilus nevus)
- PUVA lentigo
- scar lentigo