LCH affects children more often than adults. Incidence estimates in Europe range from 2.6 to 8.9 cases per million children per year.[5]Salotti J, Nanduri V, Pearce MS, et al. Incidence and clinical features of Langerhans cell histiocytosis in the UK and Ireland. Arch Dis Child. 2009 May;94(5):376-80.
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[6]Carstensen H, Ornvold K. The epidemiology of Langerhans cell histiocytosis in children in Denmark, 1975-89. Med Pediatr Oncol. 1993;21:387-8.[7]Karis J, Bernstrand C, Fadeel B, et al. The incidence of Langerhans cell histiocytosis in children in Stockholm County, Sweden 1992-2001. Proceedings of the XIX meeting of the Histiocyte Society. Philadelphia, PA: Histiocyte Society; 2003:21.[8]Alston RD, Tatevossian RG, McNally RJ, et al. Incidence and survival of childhood Langerhans cell histiocytosis in Northwest England from 1954 to 1998. Pediatr Blood Cancer. 2007 May;48(5):555-60.
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The actual annual incidence for all age groups is closer to 11 to 12 per million.[9]Berry DH, Becton DL. Natural history of histiocytosis X. Hematol Oncol Clin North Am. 1987 Mar;1(1):23-34.
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Incidence may be underestimated, because many patients with localized bone or skin disease may not be diagnosed.
Most children have single-system disease.[10]Stuurman KE, Lau L, Doda W, et al. Evaluation of the natural history and long term complications of patients with Langerhans cell histiocystosis of bone. Proceedings of the XIX meeting of the Histiocyte Society. Philadelphia, PA: Histiocyte Society; 2003. The annual incidence of multisystem LCH in the US is 0.7 cases per million children per year. Incidence is lower in black children, and higher in Hispanic children, compared with white children.[11]Ribeiro KB, Degar B, Antoneli CB, et al. Ethnicity, race, and socioeconomic status influence incidence of Langerhans cell histiocytosis. Pediatr Blood Cancer. 2015 Jun;62(6):982-7.
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Most adult patients have multisystem disease, often involving the skin and lungs.[12]Arico M, Girschikofsky M, Genereau T, et al. Langerhans cell histiocytosis in adults. Report from the International Registry of the Histiocyte Society. Eur J Cancer. 2003 Nov;39(16):2341-8.
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The mean age at diagnosis of pediatric patients is 30 months, and there is a slight male predominance.[6]Carstensen H, Ornvold K. The epidemiology of Langerhans cell histiocytosis in children in Denmark, 1975-89. Med Pediatr Oncol. 1993;21:387-8. The mean age at diagnosis of adults is 35 years.[12]Arico M, Girschikofsky M, Genereau T, et al. Langerhans cell histiocytosis in adults. Report from the International Registry of the Histiocyte Society. Eur J Cancer. 2003 Nov;39(16):2341-8.
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