(A) Summary of diverse kinase alterations discovered by next-generation sequencing techniques in LCH in the past 13 years: pie chart illustrating a composite of the diverse kinase alterations driving LCH, many of which are targetable. (B) Diagram of the MAPK and PI3K-AKT signaling pathways: description of the activation of the RAS proteins with annotation of the signaling proteins affected by genetic alterations in the histiocytic neoplasms.