Pulmonary involvement in children with Langerhans cell histiocytosis.

ABSTRACT

BACKGROUND: Pulmonary Langerhans cell histiocytosis (pLCH) is a rare disease, mostly a component of multisystemic LCH. We aimed to investigate the clinical features and treatment results in children with pLCH. METHODS: We retrospectively reviewed the clinical, radiological, and treatment data of 37 patients with pLCH, diagnosed from 1974 to 2022. RESULTS: 10% (n=37) of 367 patients with LCH had lung involvement. The median age was 1.8 years (range 0.4 & 17.7) with a male-to-female ratio of 2.3. At admission 29.7% (n=11) presented with respiratory symptoms. Imaging showed a spectrum from nodular opacities to multiple cysts. All but one patient had multisystem disease. Twenty-nine received vinblastine-containing therapy. Ten-year event-free (EFS) and overall survival (OS) rates were 47.8% and 63.3%, respectively. In children younger and older than two years of age, the 10-year EFS was 53.3% vs. 40.2% and the 10-year OS was 58.7% vs. 68.8%, respectively. In children with and without risk organ involvement, 10-year EFS was 51.9% vs. 46.3% and 10-year OS was 51.9% vs. 73.7%. CONCLUSIONS: Lung and multisystem involvement are significant concerns in LCH, highlighting the need for careful management to reduce morbidity and mortality.