Systemic Treatment of Pulmonary Langerhans Cell Histiocytosis

Pulmonary Langerhans cell histiocytosis (PLCH) requires systemic treatment when symptoms persist or worsen and smoking cessation has not achieved adequate disease control, or when cessation is not possible. This protocol addresses active, symptomatic single-system PLCH in that setting.

Systemic chemotherapy is indicated, with a specific preferred agent established for single-system PLCH that has been shown to improve lung function across multiple studies. The full regimen — including agent, cycle structure, and scheduling — is set out in the protocol.

Dosage, frequency, route, and cycle details are in the full structured regimen below.

Any degree of improvement in clinical or radiographic findings of the lungs is considered a treatment response.