A recent study involving 34 patients—comprising 26 individuals with LCH, 2 with progressive systemic JXG, 2 with RDD, and 4 presenting with presumed single-site central nervous system histiocytosis—assessed the efficacy of BRAF inhibitors (Dabrafenib) and MEK inhibitors (Trametinib). The gene discussed is BRAF; the disease is sinus histiocytosis with massive lymphadenopathy.