Konstantinou and Tournier [48] presented a case of cutaneous RDD that showed the involvement of both the head and neck region harboring the Rearranged during transfection (receptor tyrosine kinase) (RET) gene (responsible for providing instructions to produce a protein involved in cell signaling) and the MAP2K1 pathway mutations. This evidence concerns the gene MAP2K1 and sinus histiocytosis with massive lymphadenopathy.