Pathology

Langerhans cell histiocytosis

Disease

Histiocyte

Political science

Statement (logic)

Erdheim–Chester disease

Histiocytosis

Rosai–Dorfman disease

Histiocytosis X

Medicine

Mayo Clinic Proceedings

Histiocytic neoplasms, a rare and heterogeneous group of disorders, primarily include Erdheim-Chester disease, Langerhans cell histiocytosis, and Rosai-Dorfman disease. Due to their diverse clinical manifestations, the greatest challenge posed by these neoplasms is the establishment of a diagnosis, which often leads to a delay in institution of appropriate therapy. Recent insights into their genomic architecture demonstrating mitogen-activated protein kinase/extracellular signal–regulated kinase pathway mutations have now enabled potential treatment with targeted therapies in most patients.

The Mayo Clinic Histiocytosis Working Group Consensus Statement for the Diagnosis and Evaluation of Adult Patients With Histiocytic Neoplasms: Erdheim-Chester Disease, Langerhans Cell Histiocytosis, and Rosai-Dorfman Disease