[Nevocytic nevi associated elastic fibers hyperplasia: a type of "twin nevus"]

In common intradermal or compound nevi, nevocytes may be associated with other kinds of cells, tissues or lesions. In rare cases, they are associated with notable hyperplasia of the elastic fibers. CASE-REPORTS AND RESULTS: In 11 nevi (10 intradermal or compound nevi and 1 blue nevus), we observed striking hyperplasia of the elastic fibers strictly limited to the nevi, with normal aspect of the elastic fibers in the surrounding reticular dermis. These fibers were thicker than normal elastic fibers and showed tight connexions with nevus cells. This hyperplasia was not clinically relevant. It was correlated neither with the age and sex of patients nor with the site of the excised nevi. It was seen in 0.1% of excised nevi.

Hyperplasia of elastic fibers in some common nevi is a curiosity which may be classified together with other vascular, nervous, epithelial or connective twin lesions occasionally associated with the nevocytic nevi. It has to be added to the list of so-called "twin nevi".