A randomized phase2 study of bendamustine plus Rituximab for relapsing or refractory follicular lymphoma comparing 90 mg/sqm BR vs. 120 mg/sqm BR

INTERVENTION: Standerd dose bendamusutine 90mg/sqm day1‐2 rituximab 375mg/sqm day1 1 cycle of 28days Standerd dose bendamusutine 120mg/sqm day1‐2 rituximab 375mg/sqm day1 1 cycle of 28days CONDITION: Follicular lymphoma PRIMARY OUTCOME: CR INCLUSION CRITERIA: 1 Pathological diagnosis of follicular lymphoma on the basis of biopsy. 2 Patients who did not enter in partial remission (PR) by chemotherapy(except single adrenocortical hormones), or relapsed after attaining complete remission (CR) or PR.Regardless of the number and the type of ex‐chemotherapy. 3 CD20 positive. 4 With measurable lesion (>1.5cm on the CT scan) 5 Age 20 to 80 at the time of registration. 6 ECOG Performance Status 0‐2. 7 Patients who meet all the following standards. Neutrophil count : More than 1,000/mm3 Hemoglobin :>= 8.0 g/dL blood platelet count :>=75,000/mm3 AST, ALT, T‐BIL in the blood: less than 2.5 times normal level Electrocardiogram :normal or not required to be treated. 8 Expected at least 3 months survival. 9 Agree to participate in this study with written consent.