BRAF and Langerhans cell histiocytosis: BRAF is a member of the RAF kinase family of growth signal transduction protein kinases, and the BRAF V600E mutation is an important genetic event in the tumorigenesis of multiple types of cancers, including malignant melanoma, thyroid cancer, hairy-cell leukemia, Langerhans-cell histiocytosis, and Erdheim–Chester disease, but it has not received much attention in the context of T-cell lymphoma, as it is rarely reported [131].