What are melanocytic tumors?

Benign tumor (naevocellular naevus) proliferated naevic cells, small rounded eosinophilic cytoplasm w/melanin pigments, grouped into theca cells or sheets of cells going to dermis, benign if (good individualization of theca, absence of inflammatory infiltrate, presence of vertical ripening gradient, atypica and mitosis presence Melanoma (risk factors is light skin and sun exposure, initial phase of horizental extesion (intra epidermal) then vertical (infiltration of dermis), degree of dermal infiltration gives prognosis (thickness = Breslow index), aggressive tumors w/high risk of lymph node and visceral metastases.