2.1 Patients and cohorts
A total of 469 consecutive patients with newly diagnosed LCH (age
<18 years) were admitted to our center from January 1, 2017,
to December 31, 2021. Three hundred seventy patients with successfully
determined sCD25 at the time of diagnosis were eligible to be analyzed
in the study. Ninety-nine patients not assessable for sCD25 levels were
excluded from this study. Then, 359 patients who received first-line
therapy were further analyzed with prognostic significance, leaving out
11 patients who directly received BRAF inhibitor dabrafenib treatment.
We divided the 359 patients into two groups based on the year of
enrollment: the test cohort comprised 146 patients enrolled in BCH-LCH
2014 clinical trial (www. chictr. org. cn, identifier: ChiCTR2000030457)
between 2017-2018, while the validation cohort included 213 patients
entered CCHG-LCH-2019 (www. chictr. org. cn, ChiCTR1900025783) between
2019-2021. A flow diagram for patient inclusion and the study cohorts
was displayed in Supplementary Fig.S1.
The diagnosis of LCH was confirmed with histological examination and
CD1a and CD207 immunostaining. The following characteristics were
collected from our electronic medical record system and LCH disease
database for each patient: demographic information, clinical and
biological characteristics, examinations, treatment details, and
follow-up data.
This study was approved by the Beijing Children’s Hospital Ethics
Committee and was conducted in accordance with Declaration of Helsinki.
Informed consents were obtained from guardians of the patients.