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 | BRAFV600E, 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.