Biomarkers for Diagnostic, Prognostic, and Treatment Response in Adult Langerhans Cell Histiocytosis

What this Trial Is About

Adult Langerhans cell histiocytosis (LCH) is a rare disease caused by activation of the MAPK pathway due to mutations in affected tissues. It is classified as a myeloid neoplasia with inflammation. Patients with active systemic LCH may have detectable MAPK mutations in plasma DNA, while those with single organ involvement show these mutations less often. Diagnosis requires tissue biopsy, but lung imaging can sometimes suggest pulmonary LCH. The study aims to describe clinical features and identify blood biomarkers linked to prognosis and treatment response in adult LCH patients, including markers for cystic lung disease. This observational study involves collecting blood samples at the first visit, yearly follow-ups, before and after treatment, and during disease flare-ups. Biopsies may be performed if a flare occurs. The study includes adult LCH patients and control groups with lung cystic diseases, emphysema, or healthy smokers. Researchers will assess biomarkers for diagnosis, prognosis, and response to therapy, and will monitor MAPK mutations in plasma DNA during flares in single system LCH patients. Participants will undergo blood sampling and possible biopsies over up to 10 years. Researchers will describe the clinical course of LCH, evaluate biomarker performance, and track mutation presence in plasma DNA. The study includes informed consent, health insurance verification, and excludes certain vulnerable populations. Outcome measures focus on clinical phenotype description and biomarker evaluations throughout the long-term follow-up period.

Biomarkers for Diagnostic, Prognostic and of Response to Treatment in Adult Langerhans Cell Histiocytosis