Thalidomide for the Symptomatic Large Granular Lymphocytic Leukemia

Inclusion Criteria:

1. The patient fully understands the study, voluntarily participates, and signs the informed consent form (ICF);
2. The patient must meet the diagnostic criteria for LGLL;
3. The patient can be of any gender, aged 18 years or older;
4. The patient is either untreated or not properly treated previously, or has poor efficacy (not reaching PR) or relapsed after being treated with regimens not based on methotrexate/thalidomide;
5. The patient has indications for LGLL treatment, meeting at least one of the following criteria:

   1. ANC \< 0.5 × 10\^9/L, or neutropenia with recurrent infections
   2. HGB \< 100 g/L or requiring red blood cell transfusions for maintenance
   3. PLT \< 50 × 10\^9/L
   4. Concurrent autoimmune disease requiring treatment
   5. Symptomatic splenomegaly
   6. Severe B symptoms (unexplained fever, temperature over 38°C; night sweats; weight loss of 10% or more within six months)
   7. Pulmonary hypertension;
6. ECOG score of 0-2;
7. The patient's expected survival period is 6 months or more.

Exclusion Criteria:

1. Unable to understand or follow the study procedures;
2. Diagnosed or treated for malignancies other than LGLL within the past five years;
3. Non-lymphoma-related liver or kidney function impairment: ALT \> 3 times the upper limit of normal (ULN), AST \> 3 times the ULN, total bilirubin (TBIL) \> 2 times the ULN, serum creatinine clearance \< 30 ml/min;
4. Other serious medical conditions that could affect the study (e.g., uncontrolled diabetes, gastric ulcer, other serious heart or lung diseases), with the judgment resting with the investigator;
5. Caprini thrombosis analysis score indicating high risk (Appendix 2);
6. Known history of HIV infection or active HBV infection, or any uncontrolled active systemic infection requiring intravenous antibiotics; Note: Active HBV infection is defined as: a. HBV DNA ≥ 2000 IU/ml; b. ALT ≥ 2 times the ULN; c. Exclusion of hepatitis due to the disease itself, drugs, or other causes. All three conditions must be met. If a patient initially has active HBV infection and turns into inactive HBV infection after anti-HBV treatment, they can be included in the study provided they receive adequate anti-HBV treatment.
7. Patients who have undergone major surgery (excluding lymph node biopsy) within the past 14 days or are expected to undergo major surgery during the treatment;
8. Pregnant or breastfeeding women, and women of childbearing age who are not using contraception;
9. Hypersensitivity to the drugs or their components used in the study.