Children and adolescents with Langerhans cell histiocytosis (LCH) should be treated by a multidisciplinary team of health professionals who are experienced with this disease and its treatment. This multidisciplinary team approach incorporates the skills of the primary care physician, pediatric surgical subspecialists, radiation oncologists, pediatric medical oncologists/hematologists, rehabilitation specialists, pediatric nurse specialists, social workers, and others to ensure that children receive treatment, supportive care, and rehabilitation that will achieve optimal survival and quality of life. (Refer to the PDQ Supportive and Palliative Care summaries for specific information about supportive care for children and adolescents with cancer.)
Clinical trials organized by the Histiocyte Society have been accruing patients on childhood treatment studies since the 1980s. Information on centers enrolling patients on these trials can be found on the NCI Web site.
Patients with unresectable extrahepatic bile duct cancer have cancer that cannot be completely removed by the surgeon. These patients represent the majority of cases of bile duct cancer. Often a proximal bile duct cancer invades directly into the adjacent liver or into the hepatic artery or portal vein. Portal hypertension may result. Spread to distant parts of the body is uncommon, though transperitoneal and hematogenous hepatic metastases do occur with bile duct cancers of all sites. Invasion...
Because of treatment advances, the outcome for children with LCH involving high-risk organs (spleen, liver, bone marrow, and lung) has improved.[1,2] The high-risk designation comes from the high mortality rate (35%) in those who do not respond well to therapy in the first 6 weeks. The outcome for children with LCH involving low-risk organs (skin, bones, lymph nodes, and pituitary gland) has always been excellent, but the major challenge is to reduce the 20% to 30% incidence of recurrent lesions.
Children with high-risk or low-risk disease should be followed annually to document and attempt to correct adverse side effects of therapy or the disease. (Refer to the Late Disease and Treatment Effects of Childhood LCH section of this summary for more information about the incidence, type, and monitoring of late effects of childhood cancer and its therapy.)
The incidence of LCH has been estimated to be two to ten cases per million children aged 15 years or younger.[3,4] The male/female (M/F) ratio is close to one and the median age of presentation is 30 months. A report from Stockholm County, Sweden described an incidence of 8.9 cases of LCH per million children with a total of 29 cases in 10 years. A majority of these cases were diagnosed between September and February (M/F = 1.2). A 4-year survey of 251 new LCH cases in France found an unusual incidence of 4.6 per million children younger than 15 years (M/F = 1.2). Identical twins with LCH, as well as non-twin siblings or multiple cases in one family, have been reported. A survey of LCH in northwest England (Manchester) revealed an overall incidence of 2.6 cases per million child years.
Over 90% of adult pulmonary LCH occurs in young adults who smoke, often more than 20 cigarettes per day.[10,11]
Solvent exposure in parents and perinatal infections have a weak association with LCH, but there is no increase in cases after viral epidemics. An increased frequency of family members with thyroid disease has been reported.