Large, Dark Lesion on the Arm Present Since Birth

• Published in: American family physician Vol. 84; no. 11; pp. 1287 - 1288
• Main Authors: Leung, Alexander K.C., MD, Wong, Alex H.C., MD
• Format: Journal Article
• Language: English
• Published: United States American Academy of Family Physicians 01.12.2011
• Subjects: Adolescent; Asymptomatic; Diagnosis, Differential; Forearm; Genetic disorders; Humans; Internal Medicine; Male; Melanoma; Neurological disorders; Nevus, Pigmented - congenital; Nevus, Pigmented - diagnosis; Skin cancer; Skin Neoplasms - congenital; Skin Neoplasms - diagnosis; Tumors
• ISSN: 0002-838X; 1532-0650

The usual treatment for small and medium congenital melanocytic nevi is observation.4 The decision to remove a lesion is based on the malignant potential and its cosmetic outcome.4 Prophylactic excision is performed for giant congenital melanocytic nevi to lower the risk of melanoma. A conservative approach with serial photography of the nevus and close follow-up has also been recommended.2 All patients with congenital melanocytic nevi should be instructed on sun protection.1,4 Acquired melanocytic nevi are small (less than 8 mm in diameter), well circumscribed, and round or ovoid with a homogenous surface and even pigmentation. Summary Table Condition Characteristics Acquired melanocytic nevus Small, well-circumscribed, round or ovoid lesion with a homogenous surface and even pigmentation; multiple nevi present Becker nevus Asymptomatic, brownish, circumscribed macule or patch that gradually enlarges in an irregular fashion; usually occurs on one shoulder; hypertrichosis may be present Congenital melanocytic nevus Flat to mildly palpable, tan-colored lesion present at birth or soon after; tends to become raised and darken over time; hypertrichosis may be present Melanoma Malignant tumor that can present as an enlarging, asymmetric, variegated lesion with irregular border Plexiform neurofibroma Subcutaneous manifestation of type 1 neurofibromatosis; tender, firm nodules; early lesions may appear as hyperpigmentation and hypertrichosis Author disclosure: