Methotrexate and cytarabine in adult <scp>LCH</scp>: High risk, high reward and maintenance free?

Lin et al. report the long-term follow-up of a phase II trial involving 95 adult patients with Langerhans cell histiocytosis (LCH), investigating the combination of methotrexate and cytarabine (MA). After a median follow-up of 6.5 years, the study showed high response rates, with 90% overall response; 55% of patients free from an event such as disease progression, poor response or death; and 93% of patients were alive, though nearly half experienced febrile neutropenia. This prospective study helps fill gaps in understanding adult LCH treatment, indicating that fixed-duration chemotherapy can yield durable responses despite its associated risks. It emphasizes the importance of personalized treatment decisions, considering both fixed-duration chemotherapy and continuous targeted agents based on patient and disease-specific factors. Commentary on: Lin et al. Long term follow-up of methotrexate and cytarabine in adult patients with Langerhans cell histiocytosis. Br J Haematol 2025; 206:576-584.