Langerhans Cell Histiocytosis



Langerhans Cell Histiocytosis


Joseph Misdraji, MD









Langerhans cell histiocytosis in the liver features infiltration of the hepatic sinusoids by a mixture of Langerhans and non-Langerhans cells, with portal expansion and fibrosis.






Transmission electron microscopy demonstrates a Birbeck granule image, which is a trilamellar, striated tennis racket-shaped structure.


TERMINOLOGY


Abbreviations



  • Langerhans cell histiocytosis (LCH)


Synonyms



  • Histiocytosis X


  • Eosinophilic granuloma


  • Hans-Schüller-Christian disease


  • Letterer-Siwe disease


Definitions



  • Group of disorders characterized by clonal proliferation of Langerhans dendritic cells


ETIOLOGY/PATHOGENESIS


Clonal Disorder



  • Evidence of genetic aberrations favors neoplastic process



    • Loss of heterozygosity, chromosomal instability, elevated expression of cell-cycle-related proteins and oncogene products


CLINICAL ISSUES


Epidemiology



  • Incidence



    • Occurs in 4 per 1,000,000 children in United Kingdom of whom < 20% have hepatic involvement


  • Age



    • Infants and children, rarely adults


Site



  • LCH can involve single organ or multiple organs



    • Single-organ disease is most often bone or skin


  • Multisystem disease is subtyped according to involvement of “risk” organs



    • “Risk LCH” indicates involvement of liver, spleen, hematopoietic system


Presentation



  • Hepatosplenomegaly


  • Jaundice, cholestatic


  • Ascites


  • Hepatic dysfunction


Natural History



  • Permanent fibrosis of liver and lungs may occur, possibly due to “cytokine storm” produced by Langerhans cells



    • Results in pattern of sclerosing cholangitis


    • May progress to liver failure requiring transplantation


Treatment



  • Drugs



    • Etoposide, vinblastine, methotrexate


Prognosis



  • “Risk LCH” has 80% survival



    • Early therapy with nontoxic chemotherapy improves survival


    • Lack of response to chemotherapy at 6 weeks predicts poor survival


  • Reactivation usually occurs in nonrisk organs and is rarely fatal


IMAGE FINDINGS


Radiographic Findings

Jul 7, 2016 | Posted by in PATHOLOGY & LABORATORY MEDICINE | Comments Off on Langerhans Cell Histiocytosis
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