Fig. 2

Overall survival and event-free survival of adolescent LCH patients in different subgroups. A The OS and EFS of 36 adolescent LCH patients. The estimated 5-year OS rate was 94.7%, and the estimated 5-year EFS rate was 59.0%. B The EFS of adolescent LCH patients with different system involvement. The median EFS were 102.8 months, not reached, and 71.8 months for SS-s, SS-m, and MS patients, respectively. C The EFS of MS LCH patients with or without risk organ involvement. The median EFS were 16.1 months for patients with risk organ involvement, and 71.8 months for patients without risk organ involvement. LCH: Langerhans cell histiocytosis; OS: overall survival; EFS: event-free survival; SS-s: one lesion within a single system or one organ; SS-p: pulmonary as the single system involvement; SS-m: multiple lesions within one single system; MS: multiple systems involved; RO: risk organ