title: Splenomegaly unresponsive to standard and salvage chemotherapy in Langerhans cell histiocytosis: a case of extramedullary hematopoiesis.
abstract: Langerhans cell histiocytosis (LCH) is a proliferative disorder of dendritic cells which has evaded efforts to clearly define pathogenesis, diagnostic criteria, and therapeutic response markers. Strides have been made at classification with the recent development of a quantified score of disease severity. Splenic involvement is an indicator of poor prognosis, with spleen size its surrogate marker in evaluation and scoring. We describe a case of pediatric LCH with progressive splenomegaly despite treatment, which when examined at splenectomy revealed no LCH involvement but extramedullary hematopoiesis. These findings thus challenge our understanding of splenomegaly as a marker of disease.
authors.affiliation: University of Minnesota Medical School, Minneapolis, MN, USA.
authors.forename: Ellen C
authors.initials: EC
authors.lastname: Christiansen
authors.forename: Marcine
authors.initials: M
authors.lastname: Ellwein
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Neglia
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D006411:Hematopoiesis, Extramedullary; D006646:Histiocytosis, Langerhans-Cell / Q000150:complications* / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D016879:Salvage Therapy; D013156:Splenectomy; D013163:Splenomegaly / Q000209:etiology* / Q000601:surgery
chemical_list: D000970:Antineoplastic Agents