Background: Langerhans cell histiocytosis (LCH) is a group of idiopathic disorders characterized by the proliferation of specialized bone marrow-derived Langerhans cells and mature eosinophils. The estimated annual incidence ranges from 0.5-2 cases per 100,000 persons per year. The pathogenesis of LCH is unknown. The prevalence of LCH seems to be higher among whites and males. The most common complaints at presentation are those related to bone lesions. Treatment consists of surgery, chemotherapy and radiotherapy alone or in combination. The age of onset varies according to the variety of LCH. Solitary lesions may occur in bones or skin. Cutaneous lesions present with firm, painless papulonodules or vesicles.

Case report: This six-month-old baby presented with firm papulonodules on her temporal skin, but fortunately her other organs were healthy. She underwent two surgeries, separated by a one-month interval. Due to local recurrence after a short period of time, she underwent a 10-Gy dose of radiation. Her response proved good during follow-up.

Conclusion: Radiotherapy is good for controlling local recurrence in LCH, with few sequelae related to treatment.