Table 1.

Histiocytoses of the L group

Disease	Subtypes
LCH	LCH SS
	LCH lung+
	LCH MS-RO+
	LCH MS-RO−
	Associated with another myeloproliferative/myelodysplastic disorder
ICH
ECD	ECD classical type
	ECD without bone involvement
	Associated with another myeloproliferative/myelodysplastic disorder
	Extracutaneous or disseminated JXG with MAPK-activating mutation or ALK translocations
Mixed ECD and LCH

ECD, Erdheim-Chester disease; ICH, indeterminate cell histiocytosis; LCH, Langerhans cell histiocytosis; MS, multiple system; RO, risk organ; SS, single system.