The purpose of this study is to investigate efficacy and safety of GemOx(Gemcitabine and Oxaliplatin) combination with rituximab(R) as first-line treatment of elderly patients with DLBCL

Previous studies showed that the combination of rituximab, gemcitabine and oxaliplatin (R-GemOx) achieved high efficacy with a low toxicity profile in relapsed and refractory DLBCL. This regimen might be considered a putative treatment option for elderly patients. To our knowledge, the efficacy and safety of R-GemOx when given as first-line therapy in elderly patients with DLBCL remains unknown. The investigators therefore developed a two-weekly regimen of rituximab combined with GemOx regimen as first line treatment in elderly DLBCL and investigate its efficacy and safety.

Primary Outcome Measures:

• overall response rate

Secondary Outcome Measures:

• progression free survival
• overall survival
• safety and toxicity

Enrollment: 60 Study Start Date: August 2012 Primary Completion Date: Dec 2015

Inclusion criteria:

1. Histologically confirmed CD20-positive DLBCL (The germinal center B-cell like (GCB) / non-GCB subtype was determined by immunohistochemistry in paraffin-embedded tissue using CD10, BCL6 and MUM1 protein markers based on Hans's algorithm);
2. New-diagnosed and untreated;
3. Age older than 70 years or older than 60 years with ECOG PS ≥2;
4. Understand and voluntarily sign an informed consent form, able to adhere to the study visit schedule and other protocol requirements.

Exclusion Criteria:

1. Poor hepatic or renal function, defined as total serum bilirubin, transaminases or creatinine over two times of the upper limit of normal concentration;
2. Poor cardiac function greater than Grade II according to New York Heart Association Functional Classification;
3. Presence of Grade III nervous toxicity over two weeks;
4. Hepatitis B virus (HBV) load (HBV DNA) more than 1×105 copies/ml;
5. Concomitant malignancy other than DLBCL requiring treatment;
6. Concomitant with other hematologic diseases (such as leukemia, hemophilia, primary myelofibrosis) which is unsuitable to be enrolled into this clinical trial;
7. Contraindication to any drug in this regimen;
8. Active and severe infectious diseases, such as severe pheumonia or septicaemia;
9. Major surgery within three weeks;
10. Any medical, psychological or social conditions which might interfere with the investigators' assessment
11. In any conditions which investigator considered ineligible for this study.