Treatment of Becker's Nevus in the Axilla
Becker's nevus requires no treatment in most cases, as it is a benign condition with no risk of malignant transformation, and intervention is pursued only for cosmetic concerns using laser therapy with moderate efficacy. 1, 2, 3
Understanding Becker's Nevus
Becker's nevus (also called Becker's melanosis) is a benign epidermal hamartoma presenting as a unilateral hyperpigmented patch with hypertrichosis, typically appearing during adolescence or puberty, though it can be congenital. 1, 4, 5 The axilla is an uncommon location, as these lesions most frequently affect the shoulder, scapular area, and upper arms. 1
Key Clinical Features to Confirm Diagnosis
- Appearance: Well-defined hyperpigmented brownish patch with irregular borders, often with increased hair growth (hypertrichosis). 1, 4
- Size: Mean diameter of 15 cm, though variable. 1
- Timing: Usually appears around puberty, gradually darkening and enlarging over time. 1, 4
- Histology: Shows epidermal hyperkeratosis, acanthosis, increased basal layer pigmentation, and focal pigment incontinence—importantly, dermal nevus cells are never present. 1, 5
Treatment Algorithm
Step 1: Determine Need for Treatment
No treatment is medically necessary, as Becker's nevus is entirely benign with no documented cases of malignant transformation in the literature. 2 Treatment is pursued solely for cosmetic improvement if the patient desires it. 2
Step 2: If Cosmetic Treatment Desired
Laser therapy is the primary treatment modality, though outcomes are moderate and inconsistent. 3
Laser Options:
- Wavelength range: 504 to 10,600 nm have been used. 3
- Treatment sessions: Typically 1 to 12 sessions required. 3
- Combination therapy: Using lasers with different wavelengths appears to achieve better efficacy than single-wavelength treatment. 3
- Expected outcomes: Mixed results with moderate efficacy overall. 3
- Side effects: Usually mild to moderate erythema. 3
Important Caveats
- Recurrence is common: Pigmentation frequently returns after laser treatment. 3
- Patient counseling essential: Set realistic expectations about moderate efficacy and potential need for multiple sessions. 3
- No urgent referral needed: Unlike congenital melanocytic nevi, Becker's nevus does not require urgent dermatology evaluation unless diagnostic uncertainty exists. 1, 2
Associated Conditions to Screen For
Bony and soft tissue structural anomalies occur with increased frequency in patients with Becker's nevus, so consider screening for skeletal abnormalities if clinically indicated. 5