Late Onset Neutropenia and Decreased Immunoglobulin Concentration after Rituximab Combined Autotransplantation for B Cell Lymphoma.

Chemotherapy with Rituximab is widely used to treat patients with various B-cell lymphomas and auto-transplantation with Rituximab is promising strategy due to the potential for in vivo purging. However, the possibility of late onset neutropenia and immunoglobulin suppression after auto-transplantation with Rituximab has been indicated. We studied the frequency and degree of these phenomena. We performed a retrospective analysis on 26 consecutive patients at three centers during the period of January 1998 to March 2005.

Thirteen patients (Follicular 8, Marzinal zone B cell lymphoma 2, Diffuse large B 3) received auto-transplantation without Rituximab (R-) compared with 13 patients (Follicular 8, MZBCL 2, DLB 3) received auto-transplantation with Rituximab (R+). In R+ patients pripheral blood stem cells were harvested after High dose AraC followed by three times of Rituximab (375mg/m2 day -2 of AraC, day7, 14). Conditioning regimen consisted of MCEC (MCNU, CBDCA, ETOP, Cy) or TBI+Cy followed by three times of Rituximab (375mg/m2 day 0, 7, 14).

Mean immunoglobulin concentration one month after transplantation was 890 mg/dl for R- vs. 470 mg/dl for R+ (P=0.04). Lowest neutrophil numbers over 4 weeks after transplantation was 1.24X109/L for R- vs. 0.36X109/L for R+ (p=0.02). Late onset neutropenia (<0.5X109/L) were seen in three cases of R+ group, but no case in R- group. Therapy related death was seen one case in R+ group. This case showed low immunoglobulin level after transplantation and died of Pneumocystis Carinii. These data, although preliminary, indicates that the addition of Rituximab to auto-transplantation leads to decrease in immmunoglobulin and neutrophil levels after transplantation.