Langerhans Cell Histiocytosis Treatment - Presentation of LCH in Children
A study reporting outcomes for children with only low-risk organ disease (skin, bone, lymph nodes, or pituitary gland) or pulmonary plus low-risk organs revealed that patients with pulmonary involvement had a 5-year survival of 83% compared with 94% for those with only low-risk organ involvement.
Adults with pulmonary LCH who have minimal symptoms have a good prognosis, although some have steady deterioration over many years. Age older than 26 years and lower FEV1/FVC ratio and higher RV/TLC ratio are adverse prognostic variables.
Patients receiving lung transplantation for treatment of pulmonary LCH have a 77% survival rate at 1 year and 54% survival rate at 10 years, with a 20% chance of LCH recurrence.
Most patients with bone marrow involvement are young children who have diffuse disease in the liver, spleen, lymph nodes, and skin who present with significant thrombocytopenia and anemia with or without neutropenia. Others have only mild cytopenias and are found to have bone marrow involvement with LCH by sensitive immunohistochemical or flow cytometric analysis of the bone marrow. All of the bone marrow biopsy specimens (22 of 22 specimens) in one study had increased numbers of dysplasia of megakaryocytes, often with emperipolesis (active penetration by one cell into and through a larger cell). Patients with LCH who are considered at very high risk sometimes present with hemophagocytosis involving the bone marrow. The cytokine milieu driving LCH is probably responsible for the epiphenomenon of macrophage activation.
Diabetes insipidus (DI), caused by LCH-induced damage to the anti-diuretic hormone (ADH)-secreting cells of the posterior pituitary, is the most frequent endocrine manifestation in LCH. MRI scans usually show nodularity and/or thickening of the pituitary stalk and loss of the pituitary bright spot on T2-weighted images. Pituitary biopsies are rarely done and usually only when the stalk is greater than 6.5 mm or there is a hypothalamic mass. Most often the diagnosis is established by biopsying the skin, bone, or lymph node of a patient who also has pituitary abnormalities.
Approximately 4% of patients present with an apparently idiopathic presentation of DI before other lesions of LCH are identified. A review of such patients found that 51% will develop other LCH lesions diagnostic of LCH within 1 year of identifying DI. A study of 589 patients with LCH in France revealed the 10-year risk of pituitary involvement was 24%. These investigators did not see a decreased incidence of DI in chemotherapy-treated patients, but this may reflect the length of the therapy and/or the number of drugs used. Using longer therapy and more drugs, the German-Austrian-Dutch (Deutsche Arbeits-gemeinschaft f�r Leukaemieforschung und-therapie im Kindesalter [DAL]) Group found the cumulative incidence to be 12%. DI followed initial LCH diagnosis by a mean of 1 year and growth hormone deficiency occurred 5 years later.