Becker's Nevus: Clinical Features and Management
Becker's nevus is a benign cutaneous hamartoma requiring no treatment, characterized by unilateral hyperpigmented patches with hypertrichosis that typically appears during adolescence in males, with observation being the only necessary management approach.
Clinical Features
Classic Presentation
- Unilateral, irregularly shaped, hyperpigmented patch typically located on the anterior upper body, shoulder, or upper trunk 1, 2
- Hypertrichosis (increased hair growth) develops within the pigmented area, often becoming more prominent over time 1, 3
- Acneiform lesions may occasionally be present within the nevus 1
- Prevalence of 0.5% with strong male predominance 1
Age of Onset
- Most commonly appears during adolescence (peripubertal period) 1, 2, 3
- Congenital cases are rare but have been documented 4, 5
- Pigmentation and hair growth may darken and become more prominent with time 3
Atypical Presentations
- Bilateral lesions are extremely rare, though symmetrical and asymmetrical bilateral cases have been reported 2, 4
- Atypical locations including forearm and leg can occur 1
- Familial cases with autosomal dominant transmission have been rarely documented 5
Differential Diagnosis Considerations
While the provided evidence focuses on congenital melanocytic nevi, it's critical to distinguish Becker's nevus from:
- Congenital melanocytic nevus: These carry a 0.7-1.7% lifetime melanoma risk and require surveillance 6, 7
- Becker's nevus has no malignant potential and is a hamartoma, not a melanocytic lesion 1
Diagnostic Approach
Clinical Diagnosis
- Diagnosis is primarily clinical based on characteristic appearance 1, 3
- Histological examination shows hyperpigmentation of the basal layer and melanophages in the upper dermis 3
Key Distinguishing Features from Melanocytic Nevi
- No nodules or papules should be present (unlike evolving congenital melanocytic nevi) 6
- Uniform hyperpigmentation without the mottled or speckled appearance of melanocytic nevi 6
- Epidermal hamartoma rather than melanocytic proliferation 1
Management
Primary Recommendation
Observation only—no intervention is required as Becker's nevus is a benign hamartoma with no malignant potential 1, 2, 4
What NOT to Do
- Avoid ablative procedures (lasers, curettage, dermabrasion) as these can cause pigment recurrence and are unnecessary for this benign condition 6, 7
- Do not perform routine excision unless the patient requests removal for cosmetic reasons 1
- No surveillance protocol is needed unlike congenital melanocytic nevi 6, 7
Patient Counseling
- Reassure patients this is a benign condition with no cancer risk 1
- Explain that pigmentation and hair growth may increase over time, particularly during and after puberty 3
- Cosmetic treatment options (if desired) may include laser therapy for pigmentation or hair removal, though recurrence is common 6
Becker's Nevus Syndrome
When to Consider
- Developmental abnormalities occurring with Becker's nevus define Becker's nevus syndrome (BNS) 1
- Evaluate for associated anomalies including skeletal, muscular, or breast hypoplasia if syndromic features are suspected 1
Critical Pitfall to Avoid
Do not confuse Becker's nevus with congenital melanocytic nevus—the latter requires long-term surveillance for melanoma risk with annual dermatology evaluation, while Becker's nevus requires no follow-up 6, 7, 1.