Sandbox: Langerhans

• Langerhans cell histiocytosis is a rare disease that tends to affect children and adolescents.
• The incidence of Langerhans cell histiocytosis is approximately 5 per 1,000,000 individuals in the United States.
• Langerhans cell histiocytosis commonly affects individuals younger than 15 years of age.
• The median age at diagnosis is depends on the specific subtype of the disease, such as:

• Pulmonary Langerhans cell histiocytosis is usually first diagnosed among adults.
• Unifocal Langerhans cell histiocytosis and multifocal unisystem Langerhans cell histiocytosis are usually first diagnosed among individuals of 2-10 years of age.
• Multifocal multisystem Langerhans cell histiocytosis is usually first diagnosed among individuals younger than 2 years of age.

• Males are more commonly affected with Langerhans cell histiocytosis than females. The male to female ratio is approximately 2 to 1.
• Langerhans cell histiocytosis usually affects Caucasian and Hispanic individuals. African American individuals are less likely to develop Langerhans cell histiocytosis.