. 2017 Sep 27;26(145):170042. doi: 10.1183/16000617.0042-2017

TABLE 2.

Distinctive features of lymphangioleiomyomatosis (LAM) and pulmonary Langerhans cell histiocytosis (PLCH)

	LAM	PLCH
Related to smoking	Not evident	Strong
Gender predilection	Yes (female)	No
Genetic mutations	TSC1 or more frequently, TSC2	BRAF^V600E, NRAS, MAP2K1
HRCT pattern	Cystic	Nodular-cystic Cystic Nodular
Multisystem involvement	Frequent	Possible
Treatment	Sirolimus^#	Smoking cessation Steroids Vinblastine Possible role of cladribrine and BRAF inhibitors

^#: approved by the US Food and Drug Administration in 2015, recognised as orphan drug by the European Medicines Agency in 2016. HRCT: high-resolution computed tomography.