RecruitingPhase 3Drug trialThe Safety and Effectiveness of 4R-CHOP+4R vs 6R-CHOP+2R in Newly Diagnosed Patients With DLBCL in Low RiskThe Safety and Effectiveness of Four Courses of R-CHOP Plus Four Courses of Rituximab Versus Six Courses of R-CHOP Plus Two Courses of Rituximab in the Treatment of Naive, Low-risk, Non-mass Diffuse Large B-cell Lymphoma: a Multi-center, Prospective, Randomized Controlled Study