Low-dose methotrexate in therapy-resistant lichen sclerosus: first clinical experience with recurrence-free interval extension in HPV-independent vulvar intraepithelial neoplasia (HPVi VIN)

Low-dose methotrexate (MTX) has been used for corticosteroid-refractory lichen sclerosus, but its effect on differentiated vulvar intraepithelial neoplasia (dVIN) recurrence has never been reported. In this first multicenter within-patient observational study, all six continuing patients exceeded their shortest pre-MTX recurrence-free interval, and three achieved sustained reduction in topical corticosteroid use. These findings support prospective evaluation in the MERCURE trial and provide a rationale for MTX as a non-surgical treatment option in recurrent, therapy-resistant dVIN.