Ablative fractional laser therapy as treatment for Becker nevus: a randomized controlled pilot study

Becker nevus (BN) is an uncommon pigment disorder characterized by hyperpigmentation and sometimes hypertrichosis. To date, no effective treatment has been available. We sought to assess efficacy and safety of ablative 10,600-nm fractional laser therapy (FLT) in the treatment of BN. Eleven patients with BN, older than 18 years, were included in a prospective randomized controlled, observer-blinded split-lesion trial. In each patient two similar square test regions were randomized to either ablative FLT at 10 mJ/microbeam, coverage 35% to 45%, and topical bleaching (to prevent laser-induced postinflammatory hyperpigmentation), or topical bleaching alone (to allow comparison of the regions). At 3- and 6-month follow-up, clearance of hyperpigmentation was assessed by physician global assessment, reflectance spectroscopy, melanin index, patient global assessment, patient satisfaction, and histology. At 6-month follow-up, physician global assessment improved in the FLT region (P <.05). Reflectance spectroscopy, melanin index, number of melanocytes, and amount of dermal melanin did not significantly differ between the regions. Patient global assessment and patient satisfaction were 5.0 and 5.9 (visual analog scale score, 0-10), respectively. Side effects were postinflammatory hyperpigmentation (n = 3), erythema (n = 3), burning sensation (n = 3), crusting (n = 3), edema (n = 2), and blistering (n = 2). Limitations include the small number of patients, treatment in spring, possibly suboptimal laser settings, and the combined usage of FLT and a bleaching agent. Ablative FLT was moderately effective in some patients with BN. However, postinflammatory hyperpigmentation and relatively negative patient-reported outcomes still preclude ablative FLT from being a standard therapy. Larger studies with different laser settings will be required to optimize this treatment modality