langerhans cell histiocytosis (lch) is a rare disorder described as three different entities including eosinophilic granulomaof bone, the hand-schuller-christian syndrome, and letterer-siwe disease. lch is currently classified into singlesystem lch, and multisystem lch. patients with single system lch have an excellent prognosis, and are mostlytreated with local therapy. multisystem lch is subd...
