Prognostic factors in patients with diffuse large B cell lymphoma: Before and after the introduction of rituximab

This study attempted to evaluate the usefulness of the International Prognostic Index (IPI) as a prognostic model in patients treated with R-CHOP (rituximab, cyclophosphamide, vincristine, adriamycin and prednisolone) chemotherapy. We compared 279 patients with DLBCL. Among them, 183 received CHOP while 96 received R-CHOP. Results showed that there were no statistically significant differences between the two groups of patients in terms of both the patient and the lymphoma characteristics. The estimated 2-year survival was significantly higher among patients treated with R-CHOP compared to CHOP alone (85.6% vs. 64.7%, P = 0.004). Both the IPI and age-adjusted IPI were less useful as prognostic models in patients receiving R-CHOP compared to CHOP. In the multivariate analysis, age ≥ 60, elevated serum LDH, low serum albumin and advanced stages of disease were each independently associated with decreased survival in patients treated with CHOP. In contrast, among those treated with R-CHOP, only male sex and advanced stage of disease were each independently associated with decreased survival. Using these two factors, patients treated with R-CHOP could be separated into three prognostic groups with 5-year estimated survival ranging from 47% to 100% (P < 0.0001). In summary, we can conclude that with the significant improvement in survival following the use of rituximab, the relevance of previously recognized prognostic factors has to be reassessed and re-evaluated.