BRAF and Langerhans cell histiocytosis: In univariate analysis, classification as multisystem LCH with risk-organ involvement (MS-LCH RO+), Ann Arbor stage III, BRAF V600E positivity, MTV > 25.0, and TLG > 150.0 were significant risk factors for worse progression-free survival (PFS) (all p < 0.05).