A Clinical Trial of Decitabine in Relapsed or Refractory T-lymphoblastic Lymphoma

Inclusion Criteria: * age: 14\~60 years; ECOG rate ≤ 2; expected survival \> 3 months; * patients with T-lymphoblastic lymphoma diagnosed by histopathology detection; * patients ever received chemotherapy and/or radiotherapy;and can not be transplanted hematopoietic stem cells; * patients with no chemotherapy contraindications: hemoglobin ≥ 90 g/L, absolute neutrophil count ≥1.5 x 109/L, blood platelet ≥100 x 109/L, ALT and AST ≤ 2-fold upper normal limit, serum bilirubin ≤ 1.5-fold upper normal limit, serum creatinine ≤ 1.5-fold upper normal limit, serum albumin ≥ 30 g/L, normal serofibrinogen; * at least one measurable nidus; * no other severe diseases conflict with this project, cardiopulmonary function is basically normal; * the urine or blood pregnancy test of women in childbearing age must be negative in 7 days before follow-up visit; * applicable for follow-up visit; * no other antitumor adjoint therapy (including antitumor Chinese medicine, immunotherapy and biotherapy), but double phosphate anti-bone transfer therapy and other symptomatic treatment are acceptable; * understanding this study and assigning informed consent. Exclusion Criteria: * rejecting providing blood preparation; * allergic to drug in this study and with metabolic block; * rejecting adopting reliable contraceptive method in pregnancy or lactation period; * uncontrolled internal medicine disease (including uncontrolled diabetes, severe incompetence cardiac, lung, liver and pancreas); * with severe infection; * with primary or secondary central nervous system tumor invasion; * with immunotherapy or radiotherapy contraindication; * ever suffered with malignant tumor; * having peripheral nervous system disorder or dysphrenia; * with no legal capacity, medical or ethical reasons affecting research proceeding; * participating other clinical trials simultaneously; * adopting other anti-tumor medicine excluding this research; * the researchers considering it inappropriate to participate in the study.