lentiginous malignant melanoma, Breslow's depth mm
Histologic Features
- A broad (greater than 6 mm.), asymmetrical, poorly circumscribed lesion characterized by
- A proliferation of atypical melanocytes that vary in sizes and shapes
- Melanocytic nests that tend to confluence
- Single melanocytes predominating at some foci in the epidermis
- Scatter of single melanocytes and nest of melanocytes above the dermo-epidermal junction (pagetoid spread)
- Involvement of the adnexal structures in the dermis
- Melanocytic atypia and occasional necrosis of melanocytes
- Failure of maturation with descent into the dermis
- Many mitotic figures, some atypical, near the base
- Severe solar elastosis in the dermis
- Poorly distributed melanin deposition
- Signs of regression, evidenced by fibroplasia, lymphocytic infiltrate, telangiectasia, and melanophages
- Plasma cells in numbers, even at the base
- The neoplasm extends to a Breslow's depth of mm and a Clark's level
Updated Wednesday, July 31, 2013 8:30:48 PM