Prognostic Significance Of The Lymphocyte-to-monocyte Ratio And Corrected Levels Of Serum Calcium In Patients With Newly Diagnosed Multiple Myeloma

Objective(s):The purpose of this study was to investigate the significance of lymphocyte to monocyte ratio(LMR)and corrected levels of serum calcium(cCa)as prognostic markers of newly diagnosed multiple myeloma,which provide a useful reference and determin prognosis or aid clincal decison making for newly diagnosed patients.Methods:A total of 123 patients with multiple myeloma who were newly diagnosed in The Second Affiliated Hospital of Kunming Medical University from January 2013 to March 2020 were selected for this study.Receiver operating characteristic(ROC)curve was used to determine the optimal cut-off value of the variable.According to the optimal LMR cut-off value of 3.35,patients were divided into high LMR group(LMR≥3.35)and low LMR group(LMR<3.35).At the same time,the corrected levels of serum calcium was divided into high cCA group(cCa≥2.75)and low cCa group(cCa<2.75).Patients were divided into four groups for comparison according to initial diagnosis LMR and LMR in patients after four courses of treatment(LMR4):Group A(LMR≥3.35,LMR4≥3.35),Group B(LMR≥3.35,LMR4<3.35),Group C(LMR<3.35,LMR4≥3.35),group D(LMR<3.35,LMR4<3.35).Finally,a simple prognostic model was developed by combining LMR and cCa.LMR<3.35 and cCa≥2.75 were regarded as risk factors,and the patients were divided into group A(no risk factors,i.e.LMR≥3.35 and cCa<2.75),group B(1 risk factor,i.e.LMR≥3.35 and cCa<2.75 or LMR<3.35 and cCa≥2.75)and group C(2 risk factors,i.e.LMR<3.35 and cCa≥2.75).Independent sample t test,Pearson chi-square test or Mann-Whitney U test were used to evaluate the differences of various parameters,and Kaplan-Meier method and Cox regression were used for survival analysis.Results:1.The optimal threshold value of LMR was determined to be 3.35 by ROC curve,and the patients were divided into two groups(LMR≥3.35 and LMR<3.35).The LDH level of patients in the high LMR group was 204(140,231)U/L,and that of patients in the low LMR group was 271(157,365)U/L.The difference between the two groups was statistically significant(P=0.001).2.Patients were divided into two groups according to cCa(cCa≥2.75 and cCa<2.75).The creatinine level of patients in the high cCa group was 224(118,312)μmol/L and the proportion of bone marrow primitive cells was 50.7(38.9,64.8)%,while the creatinine level of patients in the low cCa group was 199(77,262)μmol/L and the proportion of bone marrow primitive cells was 34.7(17.5,51.0)%,and the difference between the two groups was statistically significant(P value was 0.007 and 0.001,respectively).And between the two groups,Durie-Salmon staging is different,high cCa group is dominated by Ⅲstaging,and the difference statistically significant(P=0.006).3.The prognostic indicators were analyzed by univariate Cox regression.LMR<3.35,Durie-Salmon Ⅲ staging and cCa≥2.75mmol/L were statistically significant(P value was 0.005,0.043 and 0.008,respectively).4.LMR<3.35,Durie-Salmon Ⅲ stage and cCa≥2.75mmol/L were included in multivariate Cox regression analysis.The results showed that LMR<3.35 and cCa≥2.75mmol/L were independent risk factors affecting the prognosis of multiple myeloma.5.A lower LMR at initial diagnosis predicted a worse outcome,with a significantly shorter overall survival(OS)compared with a higher LMR(20 vs 50.5 months,P=0.004).6.Patients were divided into groups A,B,C and D according to the changes of LMR(LMR4)after initial diagnosis and 4 courses of treatment.The OS of group A was significantly longer than that of group D,and the difference was statistically significant(55 vs 33 months,P=0.03).7.Overall survival time was significantly shorter in the high cCa group compared with the low cCa group(14.5 vs 36.5 months,P=0.006).8.Comparison of risk factor groups showed that the median OS in group A,B and C was 55,20 and 8.5 months,respectively.The prognosis of patients with no risk factors was better than those with 1-2 risk factors(group A vs B,P<0.0001;Group A vs C,P=0.001).9.Analysis of patients with multiple myeloma who achieved varying depths of remission after 4 courses of treatment showed no significant effect of early response on prognosis(P>0.05).Conclusion(s):LMR and cCa are independent risk factors affecting the prognosis of patients with multiple myeloma;The high LMR and low cCa groups had longer median survival time in Durie-Salmon Ⅲ staging;Patients with LMR≥3.35 both at initial diagnosis and after 4 courses of treatment had a better prognosis than those with LMR<3.35;There is no significant difference in prognosis of multiple myeloma with different degree of remission achieved at early stage;The simple prognostic model established by LMR and cCa can provide reference for the prognosis of newly diagnosed MM patients.