Beta-2 Microglobulin Improves the IPI Risk Stratification in Patients with Diffuse Large B-Cell Lymphoma

The beta-2 microglobulin at diagnosis has been reported to predict survival in diffuse large B-cell lymphoma (DLBCL) patients, but its prognostic significance remains controversial. We retrospectively analyzed 136 de novo DLBCL patients treated with R-CHOP in this study and found that a high beta-2 microglobulin correlated with older age, B symptoms, elevated LDH, advanced Ann Arbor stage and higher International Prognostic Index (IPI) score( p=0.034, p=0.002, p=0.018 and p <0.001, respectively). Patients with high beta-2 microglobulin showed worse overall survival (OS) (p=0.002), but not event-free survival (EFS) (p=0.148). Especially high beta-2 microglobulin could identify a subgroup of patients with poorer overall survival in low/ low-high IPI risk patients (p= 0.018). Multivariate analysis revealed that high beta-2 microglobulin, independent of IPI, indicated different survival in both OS (relative ratio [RR] 3.697; 95% confidence interval [CI], 1.324-10.321, p=0.013) and EFS (RR, 1.939; 95% CI, 1.002-3.751, p=0.049) in DLBCL patients. In conclusion, our data suggest that high beta-2 microglobulin was associated with inferior outcome in DLBCL patients treated with R-CHOP. Especially beta-2 microglobulin could identify a subgroup of DLBCL patients with poorer outcome from low/ low-high IPI risk patients, which may help to guide treatment.