Treatment of Adult Patients with Newly Diagnosed Langerhans Cell Histiocytosis (LCH) Using a Low-Dose Cytarabine Combined with Thalidomide Regimen.

AraC 100 mg/m² d1-5+ thalidomide 100mg d1-35, q35 days ,for a total of 12 cycles;followed by thalidomide 100mg, qd1-28 q28d,for a total of 12 cycles of monotherapy maintenance reatment;

Inclusion Criteria:

• Clearly diagnose and treat adult patients with multisystem or single-system multifocal LCH;
• Aged between 18 and 70 years;
• Multisystem involvement or single-system multifocal disease;
• No prior systemic treatment (patients who have only received local radiotherapy or surgery may be enrolled);
• ECOG performance status score ≤ 2;
• Judged by clinicians as suitable for treatment with this protocol;
• Patients or their families able to understand the study protocol and willing to participate in the study, providing written informed consent.

Exclusion Criteria:

• Patients with LCH involving the central nervous system;
• Single-system single-lesion LCH;
• Subjects who have undergone major surgery within 4 weeks prior to the first dose in the study;
• Subjects who have received radiotherapy within 4 weeks prior to the first dose in the study; subjects with a history of myocardial infarction within the past year;
• Patients with New York Heart Association (NYHA) class 3 or 4 congestive heart failure, or a history of NYHA class 3 or 4 congestive heart failure;
• Pregnant or lactating women;
• Abnormal liver and kidney function: creatinine level ≥176.8μmol/l (2mg/dl), transaminase and bilirubin levels more than 2 times the upper limit of normal (for LCH patients with liver involvement, bilirubin levels more than 10 times the upper limit of normal);
• Abnormal blood counts: absolute neutrophil count less than 1×10^9/L, platelet count less than 50×10^9/L;
• Patients or their families unable to understand the conditions and objectives of this study;
• Any other circumstances in which the investigator deems the patient unsuitable to participate in this trial.