OBJECTIVETo investigate the clinical features and prognosis of children with Langerhans cell histiocytosis (LCH).

METHODSA retrospective analysis was performed for the clinical data of 34 children with newly diagnosed LCH.

RESULTSThe 34 children had a median age of 14.5 months (range: 22 d to 60 months). Of all 34 children, 23 were aged 0-2 years and 11 were aged >2 years. There were 17 children in the high-risk group and 17 in the low-risk group. Thirty children received chemotherapy, and the 6-week and 12-month overall response rates were 67% (20/30) and 87% (26/30), respectively. The 3-year overall survival (OS) rate was 86%±6% and the 3-year event-free survival (EFS) rate was 64%±9%. Compared with the low-risk group, the high-risk group had significantly lower 6-week chemotherapy response rate (47% vs 87%; P<0.05), 3-year OS rate (72%±12% vs 100%; P<0.05), and 3-year EFS rate (46%±13% vs 82%±9%; P<0.05). There was no significant difference in the 12-month chemotherapy response rate between the high-risk and low-risk groups (80% vs 93; P>0.05). The high-risk group had a recurrence rate of 27% and a mortality rate of 27%. There were no recurrence or deaths in the low-risk group.

CONCLUSIONSChildren with LCH have a high overall survival rate, but the high-risk patient has a low 6-week response rate of induction chemotherapy and poor long-term prognosis.