Sean Klepper M.D.
Stephen Lyle, M.D., ...
- Proliferative (or "proliferation") nodules are rare benign lesions that develop within congenital nevi, sometimes raising suspicion for melanoma clinically.
- They generally present as smooth-surfaced brown to black papules or nodules, usually less than one centimeter in diameter.
- Ulceration or hemorrhage sometimes occur.
- They tend to gradually regress.
- Nodular proliferation of large epithelioid or spindle-shaped melanocytes with abundant cytoplasm and mild pleomorphism
- The cells of the proliferative nodule merge imperceptibly at the margin of the nodule with the cells of the surrounding congenital nevus.
- More than one mitoses per square millimeter are not permitted for the diagnosis of proliferative nodule.