Successful response of vulvar lichen sclerosus with NB‐UVB

Abstract

Dear Editor, Vulvar lichen sclerosus (VLS) is a chronic inflammatory disease of the skin, predominantly affecting the anogenital region. It is more common in female patients (10:1), with two peaks of incidence: prepubertal or postmenopausal. The pathogenesis is unknown, but autoimmune mechanisms seem to be involved. Lichen sclerosis (LE) is a chronic inflammatory disease with known malignant potential. Data are collected in the literature on its association with both squamous cell carcinoma (SC) and verrucous carcinoma of anogenital location. Both are entities highly linked to genital LE and independent of human papillomavirus (HPV) infection. Furthermore, oncogenic molecular alterations independent of HPV infection have been demonstrated that could explain the malignant potential of LE by itself. Vulvar lichen sclerosus (VLS) may be characterized by intense itching that is accompanied by whitish patches and atrophy but in 15% to 40% of cases should be asymptomatic. In more advanced stages we can find stenosis of the Introitus and labial adhesión. It is the second leading cause of nonneoplastic vulvar disease and is considered the most common cause of chronic vulvar disease with an estimated prevalence of 1:30-1:1000. A 49-year-old premenopausal woman complained color changes (Figure 1), intense itching, burning and pain in the external genital area. Sexual activity was impaired because the vaginal introitus was narrow causing intense dyspareunia. The clítoris and labia majora/ minora were fused. Candida infection and cytolytic vaginosis were ruled out with negative cytology. A biopsy was performed to confirm our diagnosis of clinical suspicion. Based on the clinical and pathological findings, we diagnosed the patient with VLS. She tried several topical treatment options, including corticosteroid ointment (clobetasol propionate twice/day 3 months and once/day 3 months), moisturization with emollients, 0.1% tacrolimus ointment, 2% amitriptyline, and 0.5% ketamine ointment. She used either systemic treatment options including antihistamines, isotretinoin, prednisona, hydroxychloroquine, doxepin, gabapentin, methotrexate, naltrexone, cyclosporine, etanercept, ustekinumab, and apremilast with little improvement. We initiated twice-weekly therapy with narrowband-UVB (NBUVB) (0.2 J/cm). Pruritus disappeared 2 months treatment started. The atrophic plaques improved (Figure 2). NB-UVB was performed for 5 months. Phototherapy was suspended for 2 months in summer so the itching worsened. When the treatment was reintroduced, the patient improved again. Nowadays the patient remains stable with 2 weekly sessions. Phototherapy is recommended in cases of failure or intolerance to standard therapies. Similar to our case, four cases of extragenital LS have been successfully reported with treatment by NB-UVB (Table 1). There are one report comparing the efficacy of highpotent topical corticosteroids with UV-A1 phototherapy in the treatment of VLS. Although resulting in a significant clinical improvement, UV-A1 phototherapy was inferior to the current gold standard treatment with topical high-potent corticosteroids. There are no reports describing treatment of VLS with NBUVB. We also should remember that a long-term application of topical corticosteroids is believed to prevent local vulvar recurrence in the context of lichen sclerosus (LS) that could develop a vulval squamous cell carcinoma (VSCC). This protective effect from malignant evolution have been stated as many researches show that carcinoma developed only in nontreated or irregularly treated VLS lesions. The mechanisms involved in the positive effects of NB-UVB on VLS are unknown, both antiinflammatory and immunosuppressive effects of NB-UVB are likely to be operating. Kreuter et al reported