CD4 and Opportunistic infection: Despite most of patients with rrDLBCL received G-CSF and preventive measures for opportunistic infections were recommended for patients whose CD4 lymphocyte count was ≤ 200/mm3, the total number of patients who developed opportunistic infections was 14 (23.7%—CMV infections 6, herpes virus infections 4, herpes zoster virus infections 4) in the phase 2 study and was 5 (13.2%) in the present study.