Combined Nevi

Christine J. Ko, MD

Key Facts

Terminology

Presence of 2 or more distinct populations of melanocytes or
Presence of 2 or more types of melanocytic nevi

Clinical Issues

Generally in young adults, size < 6 mm
Pigment of lesion often very dark brown to black or blue-black
Site: May be more common on head and neck

Microscopic Pathology

Lesion overall orderly, symmetric, and well-circumscribed
Most commonly: Compound/intradermal melanocytic nevus plus blue nevus

Top Differential Diagnoses

Blue nevus (common and cellular types)
Deep penetrating nevus
Congenital melanocytic nevus

This is an example of a combined nevus of the most common type, i.e., composed of an “ordinary” intradermal melanocytic nevus and a blue nevus. The lesion is symmetric and orderly appearing.

This higher magnification view shows the admixed melanocytic cell types. There are bland epithelioid (type A) nevus cells

interspersed with pigmented spindled to dendritic melanocytes

TERMINOLOGY

Synonyms

Melanocytic nevus with phenotypic heterogeneity, clonal nevus, nevus with focal epithelioid component, combined Spitz nevus, inverted type A nevus

Definitions

Presence of 2 or more distinct populations of melanocytes (i.e., type A melanocytic nevus cells, and spindled dendritic cells) or
Presence of 2 or more types of melanocytic nevi (i.e., intradermal melanocytic, blue)

CLINICAL ISSUES

Presentation