Inclusion Criteria:
* Age 18 -80 years old;
* Histologically confirmed transformed DLBCL;
* ECOG 0-2;
* Signed informed consent form.
* Having sufficient organ function: a) Hematopoietic function: Neutrophils ≥ 1.0 × 109/L, PLT ≥ 75 × 109/L, Hb ≥ 90g/L(unless caused by underlying disease, as judged by the investigator, such as extensive bone marrow involvement, or hypersplenism secondary to lymphoma splenic involvement); b) Liver function: bilirubin ≤1.5 times the upper limit of normal (ULN), ALT and AST\<3 x ULN, serum albumin ≥ 30 g/L; c) Renal function: serum Cr\<1.5 × ULN, creatinine clearance rate ≥ 50mL/min (calculated according to the standard Cockcroft Gault formula, if renal dysfunction is caused by tumor compression, creatinine clearance rate ≥ 30mL/min); d) Left ventricular ejection fraction (LVEF) ≥ 50% detected by echocardiography.
Exclusion Criteria:
* Individuals who are allergic to human or mouse monoclonal antibodies, or known sensitivity or allergic reaction to murine products;
* Previous organ transplantation;
* Prior treatment of any condition (e.g., cancer, rheumatoid arthritis) with cytotoxic drugs within 5 years at the time of screening or prior use of any anti-CD20 antibodies;
* Evidence of uncontrolled significant comorbidities that may affect the patient's compliance with the study protocol or affect the interpretation of the study results, including significant cardiovascular disease (such as New York College of Cardiology Class III or IV heart disease, myocardial infarction within the past 6 months, unstable arrhythmia, or unstable angina) or pulmonary disease (including history of obstructive pulmonary disease and bronchospasm);
* Recent major surgery (within 4 weeks prior to enrollment), excluding diagnostic surgery;
* Known active bacterial, viral, fungal, mycobacterial, parasitic or other infections (except for fungal infections in nail beds) at the time of study enrollment or major infections within 2 weeks before the start of the first course of treatment;
* Previous radiotherapy in the mediastinum/pericardial region;
* Active chronic hepatitis B infection (defined as HBV DNA positive): If hepatitis B virus (HBV) DNA cannot be detected during screening, patients with latent or previous hepatitis B infection (defined as positive hepatitis B surface antigen or hepatitis B core total antibody) can be included in this study. The above patients must voluntarily undergo regular HBV-DNA testing and receive appropriate antiviral treatment according to regulations.
* For patients with positive hepatitis C virus (HCV) antibody serological test, only when polymerase chain reaction (PCR) shows negative HCV-RNA can participate in this study.
* Patients with active HIV and syphilis infections;
* Pregnant or lactating women;
* The researcher determined that patients are not suitable to participate in this study.
