Outcome of Childhood Langerhans Cell Histiocytosis: Experience from a Lower-Middle Income Country

Background: Langerhans cell histiocytosis (LCH) is a rare myeloid neoplastic disorder, characterized by a heterogeneous clinical course ranging from localized, self-limiting lesions to life-threatening multisystem disease. Prognosis varies widely based on disease extent and risk organ involvement. The objective of our study was to determine the treatment outcomes and prognostic factors of childhood LCH. Methods: This retrospective observational study was conducted at the Pediatric Hematology/Oncology Department, Combined Military Hospital (CMH) Rawalpindi. Twenty-nine patients aged 0–18 years, diagnosed and treated between June 2013 and June 2023, were enrolled using non-probability consecutive sampling. Data was collected retrospectively from medical records of patients and was analyzed using SPSS version 25.0. Event-free survival (EFS) and overall survival (OS) were estimated using the Kaplan-Meier method and the log-rank test. The Cox regression analysis was performed to identify prognostic factors. Results: Of the 29 patients, 22 (75.86%) had multisystem disease, and 12 (54.54%) of them were risk organ (RO) positive. The median age at diagnosis was 18 months. Relapse occurred in 6 (20.68%) patients; all were successfully re-treated. Eleven (37.93%) patients expired, all with multisystem disease, and 9 (81.81%) with RO involvement. After a median follow-up of 80.10 months, the 5-year EFS and OS rates were 32% and 60%, respectively. RO involvement was the most significant predictor of poor outcome. Conclusion: Multisystem and RO positive cases have poor short-term outcomes, but long-term prognosis improves with survival beyond the initial 2-3 years. Risk organ involvement remains the most powerful predictor of mortality and morbidity in LCH.