Becker's Nevus: Definition and Management
What is Becker's Nevus?
Becker's nevus is a benign epidermal hamartoma—not a melanocytic lesion—that presents as a unilateral hyperpigmented patch or plaque, often with hypertrichosis, typically appearing during adolescence on the shoulder, upper back, or chest. 1, 2
- It is characterized by well-defined, irregularly bordered, brownish hyperpigmented patches with a mean diameter of 15 cm 1
- The condition predominantly affects males and usually manifests around puberty, though it can rarely be present at birth 1, 2
- Histologically, it shows epidermal hyperkeratosis, acanthosis, elongation of rete ridges, increased basal layer pigmentation, and smooth muscle hyperplasia 1, 3
- The pathogenesis involves postzygotic ACTB mutations 3
Melanoma Risk Assessment
Routine dermatology referral for melanoma surveillance is NOT indicated for Becker's nevus, as it does not confer any increased risk of melanoma. 4
- Serial clinical photography or periodic monitoring for malignant transformation is unnecessary 4
- MRI screening for malignant transformation is not recommended 4
- This is a critical distinction from congenital melanocytic nevi, which do carry melanoma risk and require surveillance 5
Management Algorithm
When No Treatment is Needed
- Reassurance is the primary management strategy for typical Becker's nevus 4
- No routine follow-up or surveillance is required from a medical standpoint 4
When Cosmetic Treatment is Desired
For patients requesting treatment of hypertrichosis, offer shaving, waxing, or electrolysis as first-line non-laser alternatives. 4
Laser Treatment Options (If Pursued)
- Laser therapy can be offered for pigmentation and hair removal, though efficacy is moderate and outcomes are inconsistent 6
- Combination laser therapy appears superior to single-modality treatment: 6, 7
- Long-pulsed 1064 nm Nd:YAG laser followed by 755 nm alexandrite laser has shown significant reduction in both hyperpigmentation and hypertrichosis 7
- Treatment typically requires multiple sessions (6-12 sessions) with wavelengths ranging from 504 to 10,600 nm 6
- Adverse effects are usually mild to moderate erythema 6
Important Caveats
- No definitive standard treatment exists for complete resolution of Becker's nevus 3
- Ablative procedures such as pigment-specific lasers, curettage, or dermabrasion should be avoided as they can cause pigment recurrence 5
- Treatment is purely cosmetic; the decision should be based on patient preference after discussing realistic expectations about moderate efficacy 6, 7
Clinical Pitfalls to Avoid
- Do not confuse Becker's nevus with congenital melanocytic nevus—the latter requires melanoma surveillance while Becker's nevus does not 4, 5
- Do not order unnecessary imaging or refer for routine dermatology surveillance 4
- Recognize that Becker's nevus syndrome (BNS) can occur with developmental abnormalities, though this is uncommon 2, 3