Langerhans cell histiocytosis (LCH) is an idiopathic monoclonal proliferation of cells with the phenotype of the Langerhans’ cell, characterized by multiorgan involvement and a chronic course, often requiring aggressive, antitumoral-like therapy. A 33-year old man presented with afour months’ history of small, translucent papules, located on the scalp, nasolabial fold, left axilae, few lesions on the trunk and nodulo-ulcerative lesions of the gums with partial loss of teeth. The lesions of the scalp and axilae were crusted and eroded. Histologically, both skin and gum biopsies revealed accumulation of large histiocytic cells in the upper dermis and at the dermal-epidermal junction.

These cells had reniform nucleus and stained positive for S100 protein, confirming the diagnosis of LCH. Treatment with 10 mg methotrexate weekly, divided in two doses of 5 mg every 12 h, for three months, resulted in complete healing of skin lesions and progressive improvement of gingival enlargement. The patient showed no cutaneous recurrence in the last 6 years. We suggest the low-dose methotrexate regimen as an alternative approach for the successful management of cutaneous forms of LCH, to avoid chemotherapy-related toxic effects.