Giant Congenital Nevus(bathing trunk nevus)

Diagnosis: Giant Congenital Nevus(bathing trunk nevus)

Giant congenital nevus with numerous nodules and tumors.

Clinical Presentation

Giant congenital nevus with numerous nodules and tumors.

Clinical History

Submitted by Alaa Saad. Originally posted September 20, 2010.

Treatment

See case discussion.

Differential Diagnosis

• Congenital melanocytic nevus (small/medium) • Melanoma • Café au lait macule (large) • Plexiform neurofibroma • Becker nevus

Key Learnings

• Congenital melanocytic nevus ≥20cm (projected adult size) — "bathing trunk nevus" when on trunk • ~5-10% lifetime risk of melanoma — higher than small CMN • Neurocutaneous melanosis: leptomeningeal melanocytosis in patients with large CMN — seizures, hydrocephalus • Satellite nevi (smaller CMN elsewhere) common and correlate with NCM risk • Prophylactic excision: controversial — does not eliminate melanoma risk (can arise in deeper tissues/CNS) • MRI brain/spine recommended for large axial CMN or multiple satellites

Tags: giant, congenital, nevusbathing, trunk, nevus, alaa saad