Prognostic significance of serum LDH and β2-MG in non-Hodgkin's lymphoma

Objective To investigate the significance of the expression of serum LDH and β2-MG in predicting survival of NHL patients and there correlations with clinical parameters. Methods The serum levels of LDH and β2-MG of 429 patients with NHL were measured by rate method and immunoturbidimetry.Besides,the clinical reference of the patients such as gender,age,B symptoms,clinical stages,extranodal sites and Karnofsky evaluation were summarized and grouped.All patients' survival status were achieved via phone and letter. All statistical analyses were performed using the SPSS program for Windows (version 16.0).Results The levels of LDH and β2-MG in age,B symptom,the advanced stage,extranodal sites≥2,Karnofsky evaluation were obviously higher than their counterpart and the difference was significant (P＜0.001). The median of LDH and β2-MG lever in age group was 229 U/L,190 U/L, 2.4 mg/L,1.7 mg/L. In B symptom was 260 U/L,192 U/L,2.3 mg/L, 1.7 mg/L. In clinical stage was 252 U/L, 175 U/L, 2.5 mg/L, 1.6 mg/L. In extranodal sites group was 278 U/L,195 U/L,2.4 mg/L,1.8 mg/L.In Karnofsky evaluation group was 250 mg/L,195 mg/L,2.2 mg/L,1.8 mg/L.LDH level of invasive lymphoma was significantly higher than that of indolent ones (median 211U/L,175 U/L,P=0.002),but there were no difference in the 32-MG level (P=0.937). There were no statistical significance about LDH and β2-MG levels in gender and cell type (P＞0.05).Overall survival rates were different between the abnormal LDH group and the normal LDH group (χ2=119.029, P＜0.001).Overall survival rates were different between the elevated β2-MG group and the normal β2-MG group (χ2 =104.733,P＜0.001).Overall survival rates of the abnormal LDH/β2-MG group was significantly lower than that of normal group (x2=192.326,P＜0.001).Multivariate analysis in Cox regression showed that LDH,β2-MG,age,clinical stages, extranodal sites, Karnmofsky evaluation and aggressive were independent prognostic factors.Conclusion The level of serum LDH and β2-MG can be taken as an auxiliary clinical index to evaluate the prognosis of the NHL patients. Key words: Lymphoma, non-Hodgkins; Lactate dehydrogenase; β2-microglobulin; Survival analysis