 The optimal treatment of primary gastric diffuse large B-cell lymphoma PG-DLBCL has not yet been defined. In most circumstances, a stomach-conserving approach is favored, but the role of radiotherapy is still a matter of debate. Recently, Rituximab along with full-dose CHOP chemotherapy has been shown to improve the outcome in elderly patients with nodal DLBCL. However, no data are available with such a therapy in patients with PG-DLBCL. Therefore, in March 2003, we initiated an ongoing, prospective, multicenter phase II study in patients with PG-DLBCL with 6 to 8 cycles of Rituximab R; 375 mgm2 plus CHOP-21 in order to evaluate the safety and efficacy of this approach. 