Proliferative Nodules Arising Within Congenital Melanocytic Nevi: A Histologic, Immunohistochemical,and Molecular Analyses of 43 Cases

Pushkar A. Phadke, Dinesh Rakheja, Long P. Le, Maria Angelica Selim, Payal Kapur, Amy Davis and Mai P. Hoang.Department of Pathology, Massachusetts General HospitalHarvard Medical School, Boston, MADepartment of Pathology, University of Texas Southwestern Medical Center,DallasDepartment of Pathology and Dermatology, Duke University Medical Center, Durham, NC.

Congenital melanocytic nevus

• Based on diameter, CNN are characterized as – Small (< 1.5 cm), – Medium (1.5-19.5 cm)– Large or giant (>20 cm in adolescents and adults or

predicted to reach 20 cm by adulthood)

• Using the prediction classification, giant nevi have also been described as comprising 9 cm on a child’s head and 6 cm on a child’s body

• Discrete dermal nodular proliferations most commonly referred to as “proliferative nodules” can be identified in congenital nevi

• atypical epithelioid tumors • atypical dermal nodules • proliferative dermal lesions

STUDY DESIGN

Atypical proliferative nodules

Ki-67

PHH3