Advances in the management of histiocytic disorders 2011

Childhood histiocytoses span a range of illnesses that can present with a small skin or single bony lesion that may spontaneously regress or a systemic disease resulting in multiorgan failure and death. For practical purposes they can be classified into four groups: Langerhans cell histiocytosis (LCH), Non-Langerhans cell histiocytoses (Non-LCH), Haemophagocytic lymphohistiocytoses (HLH) and Histiocyte lineage-related malignancies. The establishment of diagnostic, staging and response criteria for LCH has enabled a series of international randomized clinical trials to be conducted that are the basis of current evidence based treatment. However, as with non-LCH, individual cases are often difficult to manage and require expert advice. Although in most cases the disease responds to treatment many children are left with significant permanent consequences commonly affecting the skeleton and endocrine system. Familial HLH is an inherited disease in which initial remission can be gained by chemotherapeutic or immunological strategies, but then requires allogeneic stem cell transplant for cure. There are a variety of leukaemias and sarcomas that are phenotypically derived from the histiocytic lineage. Treatment and outcomes for these are generally similar to those of the wider malignant spectrum.