The annual incidence of Langerhans cell histiocytosis among adults living in Greece.

Langerhans cell histiocytosis (LCH) is a rare inflammatory myeloid neoplasia with a variable clinical course and outcome. Although there are some data regarding its incidence in children, such information in adults is lacking. To address the actual annual LCH incidence among adults, we prospectively recorded, during a 12-month period, any new case with a definitive histological diagnosis of LCH, among persons aged 18 and older living in Greece. Fourteen new cases were recorded corresponding to an annual incidence of 1.58 per million population. Female to male ratio was 1.34, and mean age at diagnosis was 43.5 years.