Ganglioside antibody profile and M protein levels during treatment course for DLBCL. Red line shows the levels of GM1 antibody, blue line shows levels of GD1B antibody, and light green line shows M protein levels. IVIG, IV immunoglobulin; R-EPOCH, rituximab plus etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin; RICE, rituximab plus ifosfamide, carboplatin, and etoposide.