Treatment of Multisystem Langerhans Cell Histiocytosis in Adults
This protocol covers the adult patient with multisystem Langerhans cell histiocytosis — defined by involvement of two or more organ systems — as well as adults with extensive or refractory multifocal single-system LCH, where systemic treatment is required.
Clinical scenario
Multisystem LCH involves two or more organ systems concurrently. This protocol also applies to extensive or refractory multifocal single-system LCH in adults. In either setting, systemic treatment is the appropriate course of management.
Treatment approach
Management includes systemic chemotherapy. For disease with specific molecular features — such as BRAF mutation status — targeted therapy with a kinase inhibitor is among the options considered. The full regimen, including agent selection, sequencing, and molecular stratification, is available in the structured protocol.
Complete protocol details are behind the button below.
Treatment goal
Disease response is evaluated using FDG-PET–based imaging after 2–3 months of therapy initiation.
References
DOI: 10.1182/blood.2021014343
Multisystem | ≥2 organ/system involvement.
For multisystem LCH or extensive/refractory multifocal single-system LCH, systemic chemotherapy agents such as cladribine, cytarabine, or vinblastine + prednisone are recommended.
For disease that is relapsed or refractory following chemotherapy, it is reasonable to consider an alternate chemotherapy agent or a kinase inhibitor based on patient-specific factors and drug availability.
For LCH refractory to first-line treatment or with end-organ dysfunction (e.g., neurologic impairment, sclerosing cholangitis), alternate conventional treatment or targeted therapies (BRAF or MEK inhibitors) should be implemented.
Because most patients will require a dose reduction and lower doses of BRAF and MEK inhibitors are quite effective, it is reasonable to start at half of the dose currently used to treat patients with melanoma.
For initially FDG PET avid LCH, it is recommended to repeat an FDG PET-based imaging study for assessment of disease response after 2–3 mo of initiation of therapy, with subsequent imaging frequency tailored individually based on the specific clinical scenario.
View source ↗