Histiocytoses are clonal disorders diseases derived from the monocyte-macrophage lineage. The Erdheim–Chester Disease (ECD) and Langerhans Cell Histiocytosis (LCH) may occur in association with overlapping clinical, histopathological and molecular features, harboring somatic MAP2K1 mutations in more than 50% of patients. BRAF and MEK inhibitors have shown to be efficacious in ECD and LCH, including responses in patients with CNS involvement. This case report describes a 59-year-old woman who presented with vemurafenib-refractory ECD/LCH overlap syndrome treated with vemurafenib/cobimetinib dual therapy, with rapidly progressing neurological involvement after its initiation. Although targeted therapy plays a crucial role in the treatment of histiocytosis, only anecdotal clinical cases treated with dual therapy have been reported in ECD or LCH and collaborative trials are needed to improve outcomes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.