The Facts About Langerhans Cell Histiocytosis "WHAT IS LANGERHANS CELL HISTIOCYTOSIS?" Langerhans cell histiocytosis (LCH), previously know as Histiocytosis- X, is a rare disorder that primarily affects children. The disease was first described in medical literature around the turn of the century. Although physicians have written about the disorder over the years, it has only been recently that it has received much attention. In 1985 physicians from all over the world, who are very interested in this disease, formed the International Histiocyte Society. Thanks to their work, we understand the disease a little better and have improved treatments. A histiocyte is a form of white blood cell which is found in every human body. Its job is to help destroy certain foreign materials and fight infections. A Langerhans cell is one of several types of histiocytes in the body. For some reason, patients with this disease have too many histiocytes (Langerhans cells). These cells accumulate in certain areas and cause problems. "WHAT KIND OF PROBLEMS CAN BE CAUSED?" A patient can have very limited involvement in only one part of the body or involvement in many different sites. Usually the disease is more serious when several sites are affected, and the patient is a young infant. Possible sites of involvement include: skin (rash) bone (single or multiple lesions) lung, liver, and spleen (dysfunction) teeth and gums (loose or lost teeth, swollen gums) ear (chronic infections or discharge ) eye (vision problems or bulging) central nervous system (excessive thirst and urination = diabetes insipidus) Also general symptoms like fever, weakness, and failure to gain weight may be present. All patients do not have all the above involvements, and it is difficult, if not impossible, for the physician to say with certainty how each patient will do with therapy. Each case is different. This uncertainty at diagnosis is very frustrating for the physician and the family. "WHAT CAUSES LANGERHANS CELL HISTIOCYTOSIS?" The cause is unknown. It may be triggered by an unusual reaction of the immune system to something commonly found in the environment. It is not a know infection or a cancer. It is not known to be hereditary. The patient did not catch it from anyone and cannot infect anyone else with the disease. "IS IT CANCER?" No. Over the years cancer treatments have been used in patients with histiocytosis. Consequently, hematologist and oncologist who treat cancer also treat children with Langerhans cell histiocytosis. However, the disease is no cancer. Radiation therapy, if used, is given in much lower doses than that which cancer patients receive. Although histiocytosis is a disease of the immune system, it is not related to AIDS. "HOW IS IT TREATED?" Treatment, if any, depends upon the individual patient. In some cases the disease will regress without any treatment at all. In others, limited surgery, small doses of radiation therapy or chemotherapy will be prescribed, depending upon the extent of the disease. Treatment is planned after a thorough evaluation of the patient to determine the extent of involvement. The goal of an overall treatment plan is to use as little treatment as possible to keep the disease under control and allow it to heal by itself. "WHAT TEST ARE DONE?" A diagnosis of LCH is usually made following a biopsy of the affected tissue. To determine the extent of the disease and subsequent treatment plan, several other tests may be done. These include blood tests, x-rays of the chest, bones (skeletal survey), and CT scans. Sometimes a biopsy is performed of the liver or bone marrow to find out the extent of the disease. "WILL PATIENTS RECOVER FROM THE DISEASE?" The vast majority of patients will survive the disease. Some may develop life-long chronic problems, while other remain symptom free. In some cases, the disease is fatal. Usually these are very young infants. They have a rapid downhill course, and do not respond to any known treatments. The physician will be able to discuss the patient's likelihood of responding and doing well. Whether or not the disease responds to treatment will often depend on the extent of organ involvement. However, it is often difficult to make definite predictions, much to the frustration of the physician and family. FACTS AT A GLANCE Langerhans cell histiocytosis is also know as: Histiocytosis-X Eosinophilic granuloma Hand-Schuller-Christian syndrome Letterer-Siwe disease There are also a number of other terms which have been used to describe syndromes which are considered to be Langerhans cell histiocytosis (LCH). These include: reticuloendotheliosis, Hasimoto-Pritzker syndrome, self-healing histiocytosis, pure cutaneous histiocytosis, Langerhans cell granulomatosis, type II histiocytosis, and non-lipid reticuloendotheliosis. It is estimated that one in 200,000 children are affected. Seventy-six percent of the cases occur before 10 years of age, but the disease can also be seen in adults of all ages. "IS HELP AVAILABLE?" YES! The Histiocytosis Association of America is an international partnership of parents, patients, physicians and friends from countries throughout the world in search of a cure. The Association's goals include public and professional information and education, patient and family support, and stimulation and support of research. There is a close working relationship with doctors and scientists in the Histiocyte Society. Langerhans cell histiocytosis is considered an "orphan disease", meaning it strikes too few people to generate government support for research. If you would like to receive more information, and help ensure that our research continues, please contact: Jeffrey Toughill Histiocytosis Association of America 302 North Broadway Pitman, NJ 08071 USA or call: 1-800-548-2758 (USA & Canada) 1-609-589-6606 (all other countries) FAX: 1-609-589-6614