Chidamide Combined With Clad/Gem/Bu With AutoSCT in R/R Diffuse Large B Cell Lymphoma

Inclusion Criteria:

1. Patients with primary refractory or recurrent diffuse large B cell lymphoma that do not qualify for treatment protocols of higher priority.
2. Relapsed patients should respond to 2nd or 3rd line salvage chemotherapy and attain at least PR before recruitment.
3. Adequate renal function, as defined by estimated serum creatinine clearance \>/=50 ml/min and/or serum creatinine \</= 1.8 mg/dL.

6\. Adequate hepatic function, as defined by serum glutamate oxaloacetate transaminase (SGOT) and/or serum glutamate pyruvate transaminase (SGPT) \</= 3 x upper limit of normal; serum bilirubin and alkaline phosphatase \</= 2 x upper limit of normal.

7\. Adequate pulmonary function with forced expiratory volume at one second (FEV1), forced vital capacity (FVC) and diffusing capacity of lung for carbon monoxide (DLCO) \>/= 50% of expected corrected for hemoglobin.

8\. Adequate cardiac function with left ventricular ejection fraction \>/= 50%. No uncontrolled arrhythmias or symptomatic cardiac disease.

9\. Performance status 0-1. 10. Negative Beta diffusing capacity of lung for carbon monoxide (HCG) text in a woman with child-bearing potential, defined as not post-menopausal for 12 months or no previous surgical sterilization

Exclusion Criteria:

1. Central nervous system lymphoma
2. Patients relapsed after ASCT
3. Bone marrow was involved by lymphoma
4. Patients with active hepatitis B or C(HBV DNA \>/=10,000 copies/mL).
5. Active infection requiring parenteral antibiotics
6. HIV infection, unless the patient is receiving effective antiretroviral therapy with undetectable viral load and normal cluster of differentiation 4 (CD4) counts
7. Evidence of either cirrhosis or stage 3-4 liver fibrosis in patients with chronic hepatitis C or positive hepatitis C serology.
8. Patients with a cQT longer than 500 ms