Lichen sclerosus: incidence and risk of vulvar squamous cell carcinoma
Menée aux Pays-Bas à partir des données portant sur 3 038 femmes atteintes d'un lichen scléreux diagnostiqué entre 1991 et 2011, cette étude de cohorte évalue l'association entre cette maladie inflammatoire cutanée chronique affectant la région anogénitale et le risque de carcinome épidermoïde de la vulve
Background The association between lichen sclerosus (LS) and vulvar squamous cell carcinoma (VSCC) has long been recognized, but large epidemiological studies are lacking. Methods Data of women diagnosed with vulvar pathology in the Netherlands were retrieved from the Dutch Pathology Registry. All vulvar pathology reports of this historical cohort were reviewed to construct a research database, including 3038 women with LS diagnosed between 1991 and 2011. The incidence rate of LS and the cumulative incidence of VSCC among women with LS were estimated. Results Between 1991 and 2011, the incidence rate of LS increased from 7.4 to 14.6 per 100,000 woman-years. The median age at time of LS diagnosis was 59.8 years and the cumulative VSCC incidence was 6.7%. The 10-year VSCC incidence in women with LS was associated with concurrent vulvar intraepithelial neoplasia (VIN) (18.8% in women with VIN and 2.8% in women without VIN) and age at time of LS diagnosis (5.9% in women of {greater than or equal to}70 years, 3% in women between 50 and 70 years and 1.8% in women < 50 years). The effects of presence of VIN and age remained significant in adjusted Cox regression analysis. Conclusion This historical cohort showed a nearly 100% increase in incidence of LS between 1991 and 2011. Concurrent VIN and age {greater than or equal to}70 at time of LS diagnosis are important risk factors for vulvar cancer development. Impact The incidence of LS is rising and special attention is needed in particular in women with concurrent VIN because of their high risk of cancer.