S1106 Rituximab With Combination Chemotherapy or Bendamustine Hydrochloride Followed by Consolidation Chemotherapy and Stem Cell Transplantation in Older Patients With Previously Untreated Mantle Cell Lymphoma

RATIONALE: Monoclonal antibodies, such as rituximab, can block cancer growth in different ways. Some find cancer cells and help kill them or carry cancer-killing substances to them. Others interfere with the ability of cancer cells to grow and spread. Drugs used in chemotherapy also work in different ways to kill more cancer cells or stop them from growing. It is not yet known whether rituximab is more effective with combination chemotherapy or bendamustine hydrochloride in treating patients with mantle cell lymphoma undergoing peripheral blood stem cell transplantation. PURPOSE: This randomized phase II trial studies how well giving rituximab together with combination chemotherapy or bendamustine hydrochloride followed by consolidation chemotherapy and peripheral blood stem cell transplantation works in treating older patients with previously untreated mantle cell lymphoma.