Report of Seven Cases of Langerhans Cell Histiocytosis in a Single Hospital in Japan

Langerhans cell histiocytosis (LCH), which shows a variable clinical presentation, is a disease that involves the proliferation of histiocytes. LCH occurs at any age and can affect a single system or multiple systems. The successful and accurate diagnosis of cases involving multiple organs requires a multidisciplinary approach. Since LCH receives limited attention, failure to recognize this disease in the early pediatric age can result in progression into adulthood. This study presents the clinical manifestations, imaging findings, pathological and cytological features, treatment strategies and prognoses of seven cases of LCH that are managed in a single hospital over the last 12 years. The ages of the patients ranged from 1 to 58 years. The sites at which LCH developed included the skin, lung, bone, lymph nodes and brain: one patient (adult male) had single-system/single-site LCH, three patients (adult male, adult female and girl) had single-system/multi-site LCH and three patients (adult female and two girls) had multi-system/multi-site LCH. BRAF V600E mutation was suggested in an adult female with multi-system/multi-site LCH and an adult male with single-system/multi-site LCH. We also discuss the pathogenesis and review the relevant literature. J Med Cases. 2019;10(7):209-217 doi: https://doi.org/10.14740/jmc3325