Phase II Study Comparing LR-GEM to R-GEM-P in Second-line Treatment of Diffuse Large B-cell Lymphoma (LEGEND)

Objectives: Primary To assess the complete response rate to LR-GEM (lenalidomide, rituximab, gemcitabine and methylprednisolone) and R-GEM-P (rituximab, gemcitabine,cisplatin and methylprednisolone) following 3 cycles of induction treatment as secondline therapy for patients with Diffuse Large B-cell Lymphoma. To investigate in both arms: * Overall response rate following 3 cycles of induction treatment evaluated by IWG 2007 criteria * Event-free survival * Overall survival * Rate of successful stem cell harvest * Toxicity * Subgroup analyses will be performed on the primary endpoint by cell-of-origin immunohistochemical subtype using the Choi method\[2\] (GCB vs non-GCB), morphological subtype (centroblastic vs immunoblastic vs other), IPI (0-1 vs ³2),and previous response to treatment (£12 vs \> 12 months), and eligibility for ASCT at randomisation. Treatment: LR-GEM: lenalidomide plus rituximab, gemcitabine and methylprednisolone every 28 days. R-GEM-P: rituximab, gemcitabine, methylprednisolone and cisplatin every 28 days. Assessment Schedule: * Patients will be reviewed at baseline and prior to each scheduled dose of treatment for toxicity * Radiological tumour assessment will be done with contrast-enhanced CT scan after the 1st and 3rd cycles in both arms. * PET/CT scan will be performed at baseline and upon completion of induction treatment (3-4 weeks after last dose of chemotherapy). If PET/CT scan is performed with a contrast-enhanced CT, then patients do not need a separate CT scan. * Follow up after completion of induction treatment will be at 3 monthly intervals for the first 12 months in Arm A and at monthly intervals for the first 12 months for patients in Arm B. Thereafter follow up in both Arm A and B will be at 6 monthly intervals for 2 years, then annually up until 5 years in total. * CT scan at 3 \& 12 months post induction treatment in both arms * Following disease progression patients will be followed for survival every 3 months until death