Spitzoid Melanocytic Neoplasm: Diagnostic Challenges and Management

Spitzoid melanocytic neoplasms are a spectrum of lesions with overlapping features of Spitz nevus (benign, usually pediatric) and melanoma (malignant). Histologic distinction can be difficult.

Key Features

• Spitz nevus: Symmetrical, sharp borders, uniform epithelioid/spindle cells, Kamino bodies, no deep mitoses.
• Spitzoid melanoma: Asymmetry, poor circumscription, cytologic atypia, deep mitoses, ulceration, invasive growth.
• Atypical Spitz tumor: Intermediate; uncertain malignant potential.

Diagnostic Approach

• Excisional biopsy with adequate margins
• Expert dermatopathology review (often second opinion)
• Ancillary: FISH, CGH, NGS for genomic classification (e.g., HRAS, kinase fusions, TERT promoter)

Management

• Benign Spitz nevus: Complete excision, surveillance
• Atypical: Wider excision, sentinel node biopsy debated
• Melanoma: Staging (Breslow, ulceration, SLNB), per NCCN guidelines

Multidisciplinary tumor board review recommended for ambiguous cases.