Chidamide Combined With PECM in Relapsed or Refractory Peripheral T-cell Lymphoma (PTCL)

Inclusion Criteria: 1. Histopathologically confirmed peripheral T-cell lymphoma (PTCL) patients; 2. Patients who have had at least one systemic treatment (including chemotherapy, hematopoietic stem cell transplantation, etc.) who have not remission or relapsed after remission; 3. For various reasons can not be hematopoietic stem cell transplantation in patients; 4. The age of 18-75 years old, male, female open; 5. ECOG (Eastern Cooperative Oncology Group) physical scoring 0-1 points; 6. Absolute value of neutrophil≥1.5 × 109 / L, platelet≥90 × 109 / L, hemoglobin≥90g / L; 7. The expected survival time ≥ 3 months; 8. No radiotherapy, chemotherapy, targeted therapy or hematopoietic stem cell transplantation were performed within 4 weeks prior to enrollment. 9. Voluntary signature of written informed consent. Exclusion Criteria: 1. Pregnancy, breastfeeding women and unwilling to take contraceptive measures of reproductive age patients; 2. B-mode ultrasonography showed that the width of end-diastolic pericardial dark area was ≥10mm; 3. Patients receiving organ transplants; 4. Patients receiving symptomatic treatment of pre-bone marrow toxicity within 7 days prior to enrollment; 5. Patients with active bleeding; 6. Liver function abnormalities (total bilirubin\> 1.5 times the upper limit of normal, ALT( alanine aminotransferase) / AST (Aspartate aminotransferase)\> 2.5 times the upper limit of normal or hepatic involvement of ALT / AST\> 5 times the upper limit of normal), renal dysfunction Creatinine\> 1.5 times the upper limit of normal), electrolyte abnormalities; 7. Persons with mental disabilities / those who can not obtain informed consent; 8. Patients with drug abuse and long-term alcohol abuse that may affect the evaluation of test results; 9. The investigators determined that they were not fit to participate in the trial.