Treatment of Langerhans Cell Histiocytosis Involving the Brain in Adults
Langerhans cell histiocytosis (LCH) with involvement of the brain parenchyma (CNS) in an adult patient represents a distinct clinical scenario that shapes both treatment selection and response monitoring.
Clinical Scenario
This protocol applies to adult patients with LCH in whom disease has extended to the brain parenchyma. CNS involvement is a defining feature that influences which treatments are considered and how response is assessed.
Treatment Approach — Partial Overview
Management in this setting may include targeted therapy guided by molecular tumor characteristics, or an alternate conventional chemotherapy agent. The full treatment algorithm, selection criteria, and sequencing are available in the structured protocol.
Response Assessment Goal
Disease response is evaluated using FDG-PET-based imaging, typically reassessed after the first months of treatment to guide further management.
References
DOI: 10.1182/blood.2021014343
- For LCH involving the brain parenchyma, first-line treatment with chemotherapy with cladribine or cytarabine is recommended.
- 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.
- The treatment data on adults with neurodegenerative disease are lacking, but BRAF/MEK-inhibitor- or cytarabine-based chemotherapy may be preferred based on limited pediatric experience.
- 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.