ABSTRACT
<p><b>OBJECTIVE</b>To investigate the clinical significance of BRAF-V600E mutation in children with Langerhans cell histiocytosis (LCH).</p><p><b>METHODS</b>Real-time fluorescence quantitative PCR was used to detect BRAF-V600E mutation in paraffin-embedded tissue samples from 26 children with LCH. A retrospective analysis was performed for the association of BRAF-V600E mutation with clinical features and prognosis of children with LCH.</p><p><b>RESULTS</b>Of the 26 children, 25 received standard chemotherapy, with a 2-year overall survival (OS) rate of 100% and a 2-year event-free survival (EFS) rate of 88%. Of the 26 pathological samples, 18 (70%) came from bone tissue, and the positive rate of BRAF-V600E mutation reached 50% (13/26). The positive rate of BRAF-V600E gene mutation was not associated with age, sex, affected organ, clinical classification, early treatment response, recurrence, and 2-year OS and EFS rates of the children with LCH (P>0.05), but it was associated with clinical grouping of LCH (P<0.05).</p><p><b>CONCLUSIONS</b>Children with LCH tend to have a high OS rate and a high incidence rate of BRAF-V600E mutation. BRAF-V600E mutation is associated with clinical grouping of LCH.</p>