Impact of occult bone marrow involvement on the outcome of rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone therapy for diffuse large B-cell lymphoma

Abstract

We assessed the prognostic impact of occult bone marrow involvement, determined by flow cytometry and/or polymerase chain reaction, in a population of 117 consecutive patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) treated with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP). Twenty-four (20.5%) had morphologically diagnosed and 16 (13.7%) had occult marrow involvement, and 77 (65.8%) had no marrow involvement. Although the pretreatment characteristics of the negative or occult marrow involvement group were similar, severe hematological toxicity after R-CHOP was more frequent in the occult marrow involvement group. Progression-free survival (PFS; p = 0.015) and overall survival (OS; p = 0.035) for the occult marrow involvement group were significantly shorter than those for the negative group, and were comparable to those of the morphologic marrow involvement group, independent of the International Prognostic Index score for PFS. Occult bone marrow involvement predicts severe hematological toxicity and negatively impacts on the PFS and OS of R-CHOP therapy.

Keywords::

• Diffuse large B-cell lymphoma
• flow cytometry
• occult bone marrow involvement
• polymerase chain reaction
• rituximab

Acknowledgements

The authors would like to thank all the physicians in Kobe City Medical Center General Hospital for the many useful comments and for their help in general. We would also like to thank Kyoko Tanaka and Natsumi Nomoto for their technical assistance.

Potential conflict of interest

Disclosure forms provided by the authors are available with the full text of this article at www.informahealthcare.com/lal.

This work was supported in part by the Kasahara Foundation for the Promotion of Cancer Research, Kobe City Medical Center General Hospital.