Malignant Cellular Blue Nevus (Melanoma Arising in Cellular Blue Nevus)
David Cassarino, MD, PhD
Key Facts
Terminology
Malignant dermal-based melanocytic neoplasm with associated cellular blue nevus or features simulating cellular blue nevus
Clinical Issues
Very rare tumor
Usually occurs in adults
Complete and wider surgical excision is necessary for local removal
Originally thought to be very aggressive, but recent reports may indicate a lower malignant potential
Microscopic Pathology
Cellular, dermal-based, nodular melanocytic tumor
Often asymmetric, appears poorly circumscribed
Cytologic atypia is usually very marked
Mitotic figures present, often atypical
May show areas of necrosis
Areas of benign cellular blue nevus may be present
 Malignant blue nevus at low magnification appears similar to a cellular blue nevus, with lobules of pale-staining cells  surrounded by darker-staining pigmented spindle cells and melanophages  . |
 High magnification of a malignant cellular blue nevus shows a densely cellular area composed of fascicles of hyperchromatic-staining cells with multiple mitotic figures  . |
TERMINOLOGY
Abbreviations
Malignant cellular blue nevus (MCBN)
