LCH is not in fact cancer, although in its more serious forms it can behave like cancer, and is therefore treated by cancer specialists.
Langerhans refers to the doctor who described the condition. A histiocyte is a normal cell which is part of the immune system and is found in many parts of the body especially in the bone marrow, the blood stream, the skin, the liver, the lungs, the lymph glands and the spleen. In LCH the histiocytes move into tissues where they are not normally found and cause damage to those tissues. LCH is divided into two groups:
Single system LCH, when the disease affects only one part of the body.
Multi system LCH, when it affects more than one part of the body.