this study included 189 patients who were diagnosed with mm between 2001 and 2011 at the asan medical center , seoul , korea .
disease was considered to be plasmablastic when > 30% of myeloma cells in the bm biopsy exhibited plasmablastic morphology .
all patients met the following criteria : bm involvement ; no previous treatment ; no previous history of other malignancies , transplantation or immunosuppression ; no anti - human immunodeficiency virus antibodies ; and availability of laboratory and radiologic data and follow - up information .
amc and alc were obtained from routine complete blood count ( cbc ) with a four - part differential ( lymphocytes , monocytes , eosinophils , and neutrophils ) using a sysmex automated hematology analyzer ( model e-4000 , se-9000 or xe-2100 , sysmex co. , kobe , japan ) , which was performed at the time of the diagnosis.19 overall survival ( os ) was defined as the time between the date of diagnosis and the date of death from any cause . for living patients , os was defined as the time between diagnosis and the last follow - up date .
os was analyzed using the kaplan - meier method and log - rank testing was used to compare groups .
median follow - up with a 95% confidence interval was calculated using the reverse kaplan - meier method.20 multivariate analyses of demographic and clinical characteristics prognostic for os were performed using the cox proportional hazards regression model .
the maximal chi - square method was adapted to evaluate the cutoff points in the dataset that best segregated patients into poor and good prognosis subgroups ( based on the likelihood of surviving ) , with the log - rank test as statistic used to measure the strength of the grouping .
( r development core team , vienna , austria ; http://www.r-project.org ) , was used to identify the optimal cut - off points for alc , amc and the alc / amc ratio.21,22 correlations between alc , amc , and the alc / amc ratio with categorical variables were analyzed using pearson 's chi - square test or fisher 's exact test , and the mann - whitney u test was used to evaluate associations with continuous variables .
all statistical analyses were performed using the spss ver . 18.0 ( spss inc . ,
. a p - value of .05 was considered to be statistically significant . the institutional review board ( irb ) of asan medical center ( seoul , korea ) approved this study protocol and provided all necessary ethical permissions .
this study included 189 patients who were diagnosed with mm between 2001 and 2011 at the asan medical center , seoul , korea .
disease was considered to be plasmablastic when > 30% of myeloma cells in the bm biopsy exhibited plasmablastic morphology .
all patients met the following criteria : bm involvement ; no previous treatment ; no previous history of other malignancies , transplantation or immunosuppression ; no anti - human immunodeficiency virus antibodies ; and availability of laboratory and radiologic data and follow - up information .
amc and alc were obtained from routine complete blood count ( cbc ) with a four - part differential ( lymphocytes , monocytes , eosinophils , and neutrophils ) using a sysmex automated hematology analyzer ( model e-4000 , se-9000 or xe-2100 , sysmex co. , kobe , japan ) , which was performed at the time of the diagnosis.19
overall survival ( os ) was defined as the time between the date of diagnosis and the date of death from any cause . for living patients
, os was defined as the time between diagnosis and the last follow - up date .
os was analyzed using the kaplan - meier method and log - rank testing was used to compare groups .
median follow - up with a 95% confidence interval was calculated using the reverse kaplan - meier method.20 multivariate analyses of demographic and clinical characteristics prognostic for os were performed using the cox proportional hazards regression model .
the maximal chi - square method was adapted to evaluate the cutoff points in the dataset that best segregated patients into poor and good prognosis subgroups ( based on the likelihood of surviving ) , with the log - rank test as statistic used to measure the strength of the grouping .
( r development core team , vienna , austria ; http://www.r-project.org ) , was used to identify the optimal cut - off points for alc , amc and the alc / amc ratio.21,22 correlations between alc , amc , and the alc / amc ratio with categorical variables were analyzed using pearson 's chi - square test or fisher 's exact test , and the mann - whitney u test was used to evaluate associations with continuous variables .
the institutional review board ( irb ) of asan medical center ( seoul , korea ) approved this study protocol and provided all necessary ethical permissions .
the mean age of the 189 patients with mm in the study was 60 years ( range , 29 to 84 years ) , and the male to female ratio was 1.077:1 .
paraprotein type was determined by immunoelectrophoresis ; igg was the most common ( n=95 , 50.3% ) , followed by light chain ( n=48 , 25.4% ) , iga ( n=34 , 18% ) , igd ( n=7 , 3.7% ) , and igm ( n=5 , 2.6% ) .
of the 189 patients , 57 ( 30.2% ) exhibited plasmablastic disease morphology . punched - out , osteolytic bone lesions ( > 3 lesions ) were identified in 96 patients ( 50.8% ) . following diagnosis ,
patients were treated with chemotherapy ( 47.1% ) , radiotherapy ( 6.3% ) , chemotherapy followed by asct ( 35.4% ) , or conservative treatment ( 11.1% ) . at the time of analysis ,
146 patients ( 77.2% ) had died of mm , and the estimated 5-year os was 26% . at the time of diagnosis ,
the median amc was 372 cells/l ( range , 41 to 2,040 cells/l ) , the median alc was 1,581 cells/l ( range , 319 to 5,742 cells/l ) and the median alc / amc ratio was 4 ( range , 0.83 to 33 ) .
the patients were divided into two groups according to alc , amc , and the alc / amc ratio at diagnosis . cut - off points for the division of groups , chosen according to the results of maximal chi - square analysis to best segregate patients , were as follows : alc 1,400 cells/l , amc 490 cells/l , and an alc / amc ratio of 2.9 .
one hundred and fifteen patients ( 60.8% ) belonged to the high alc ( 1,400 cells/l ) group , 57 patients ( 30.2% ) to the high amc ( 490 cells/l ) group and 135 patients ( 71.4% ) to the high alc / amc ratio ( 2.9 ) group .
the low alc , high amc , and low alc / amc ratio groups were associated with poor prognostic factors such as high international staging system ( iss ) stage , plasmablastic morphology , hypoalbuminemia and high 2-microglobulin ( 2 m ) .
patients with a low alc at diagnosis were more likely to present with a high iss stage ( p=.004 ) , plasmablastic morphology ( p=.027 ) , hypoalbuminemia ( p=.004 ) , anemia ( p=.005 ) , low platelets ( p=.001 ) , and leukopenia ( p=.001 ) .
patients with a high amc at diagnosis were more likely to be male ( p<.0001 ) and present with leukocytosis ( p<.0001 ) and high 2 m ( p=.015 ) , serum creatinine ( p=.014 ) and platelets ( p=.028 ) .
patients with a low alc / amc ratio at diagnosis were more likely to present with plasmablastic morphology ( p=.008 ) and leukocytosis ( p=.003 ) , and be male ( p=.011 ) ( table 1 ) .
the median follow - up period was 938 days ( range , 2 to 5,011 days ) .
univariate analysis showed that low alc , high amc , and low alc / amc ratio were correlated with poor os ( p=.002 , p=.038 , and p=.001 , respectively ) ( fig .
the 5-year os rate was also shorter in the low alc ( 17% vs 33% in the high alc group ) , high amc ( 18% vs 30% in the low amc group ) , and low alc / amc ratio groups ( 13% vs 31% in the high alc / amc ratio group ) .
univariate analyses also showed that other factors related to poor os included plasmablastic morphology ( p=.016 ) , older age ( 65 years ; p=.001 ) , high iss stage disease ( p<.0001 ) , high durie - salmon stage ( p<.0001 ) , high 2 m ( p<.0001 ) , hypoalbuminemia ( p=.009 ) and treatment without asct ( p<.0001 ) ( table 2 ) .
multivariate analysis including alc , amc , morphology , age , iss stage , durie - salmon stage , and treatment type showed that only treatment type ( asct vs no asct ) was an independent prognostic factor for os ( p=.001 ) ; alc and amc were not statistically significant ( p=.106 and p=.107 , respectively ) .
multivariate analysis including the alc / amc ratio , morphology , age , iss stage , durie - salmon stage , and treatment type showed that the alc / amc ratio and treatment type were both independent prognostic markers ( p=.047 and p=.001 , respectively ) ( table 3 ) .
we also assessed alc , amc and the alc / amc ratio in patients subdivided for factors that can affect prognosis and treatment selection ( such as asct vs no asct , age , sex , and iss ) to determine whether they could predict os . among patients who did not undergo asct , those with low alc , high amc , and low alc / amc ratio had significantly shorter os ( p=.029 , p=.025 , and p=.003 , respectively ) , but patients who received asct did not show significant differences in survival ( p=.221 , p=.323 , and p=.343 , respectively ) ( fig .
2 ) . when we stratified patients according to age , sex , and iss , low alc
was associated with poor os in patients who were < 65 years - old ( p=.009 ) , male ( p=.001 ) , or had iss stage ii disease ( p=.031 ) .
high amc was associated with poor survival in the iss stage i group ( p<.0001 ) .
low alc / amc ratio was associated with poor survival in patients who were < 65 years - old ( p=.008 ) , male ( p=.018 ) , or had iss stage i ( p=.017 ) or stage iii disease ( p=.010 ) ( table 4 ) .
the mean age of the 189 patients with mm in the study was 60 years ( range , 29 to 84 years ) , and the male to female ratio was 1.077:1 .
paraprotein type was determined by immunoelectrophoresis ; igg was the most common ( n=95 , 50.3% ) , followed by light chain ( n=48 , 25.4% ) , iga ( n=34 , 18% ) , igd ( n=7 , 3.7% ) , and igm ( n=5 , 2.6% ) .
of the 189 patients , 57 ( 30.2% ) exhibited plasmablastic disease morphology . punched - out , osteolytic bone lesions ( > 3 lesions ) were identified in 96 patients ( 50.8% ) . following diagnosis ,
patients were treated with chemotherapy ( 47.1% ) , radiotherapy ( 6.3% ) , chemotherapy followed by asct ( 35.4% ) , or conservative treatment ( 11.1% ) . at the time of analysis ,
146 patients ( 77.2% ) had died of mm , and the estimated 5-year os was 26% . at the time of diagnosis ,
the median amc was 372 cells/l ( range , 41 to 2,040 cells/l ) , the median alc was 1,581 cells/l ( range , 319 to 5,742 cells/l ) and the median alc / amc ratio was 4 ( range , 0.83 to 33 ) .
the patients were divided into two groups according to alc , amc , and the alc / amc ratio at diagnosis . cut - off points for the division of groups , chosen according to the results of maximal chi - square analysis to best segregate patients , were as follows : alc 1,400 cells/l , amc 490 cells/l , and an alc / amc ratio of 2.9 .
one hundred and fifteen patients ( 60.8% ) belonged to the high alc ( 1,400 cells/l ) group , 57 patients ( 30.2% ) to the high amc ( 490 cells/l ) group and 135 patients ( 71.4% ) to the high alc / amc ratio ( 2.9 ) group .
the low alc , high amc , and low alc / amc ratio groups were associated with poor prognostic factors such as high international staging system ( iss ) stage , plasmablastic morphology , hypoalbuminemia and high 2-microglobulin ( 2 m ) .
patients with a low alc at diagnosis were more likely to present with a high iss stage ( p=.004 ) , plasmablastic morphology ( p=.027 ) , hypoalbuminemia ( p=.004 ) , anemia ( p=.005 ) , low platelets ( p=.001 ) , and leukopenia ( p=.001 ) .
patients with a high amc at diagnosis were more likely to be male ( p<.0001 ) and present with leukocytosis ( p<.0001 ) and high 2 m ( p=.015 ) , serum creatinine ( p=.014 ) and platelets ( p=.028 ) .
patients with a low alc / amc ratio at diagnosis were more likely to present with plasmablastic morphology ( p=.008 ) and leukocytosis ( p=.003 ) , and be male ( p=.011 ) ( table 1 ) .
the median follow - up period was 938 days ( range , 2 to 5,011 days ) .
univariate analysis showed that low alc , high amc , and low alc / amc ratio were correlated with poor os ( p=.002 , p=.038 , and p=.001 , respectively ) ( fig .
the 5-year os rate was also shorter in the low alc ( 17% vs 33% in the high alc group ) , high amc ( 18% vs 30% in the low amc group ) , and low alc / amc ratio groups ( 13% vs 31% in the high alc / amc ratio group ) .
univariate analyses also showed that other factors related to poor os included plasmablastic morphology ( p=.016 ) , older age ( 65 years ; p=.001 ) , high iss stage disease ( p<.0001 ) , high durie - salmon stage ( p<.0001 ) , high 2 m ( p<.0001 ) , hypoalbuminemia ( p=.009 ) and treatment without asct ( p<.0001 ) ( table 2 ) .
multivariate analysis including alc , amc , morphology , age , iss stage , durie - salmon stage , and treatment type showed that only treatment type ( asct vs no asct ) was an independent prognostic factor for os ( p=.001 ) ; alc and amc were not statistically significant ( p=.106 and p=.107 , respectively ) . multivariate analysis including the alc / amc ratio , morphology , age , iss stage , durie - salmon stage , and treatment type showed that the alc / amc ratio and treatment type were both independent prognostic markers ( p=.047 and p=.001 , respectively ) ( table 3 ) .
we also assessed alc , amc and the alc / amc ratio in patients subdivided for factors that can affect prognosis and treatment selection ( such as asct vs no asct , age , sex , and iss ) to determine whether they could predict os . among patients who did not undergo asct , those with low alc , high amc , and low alc / amc ratio had significantly shorter os ( p=.029 , p=.025 , and p=.003 , respectively ) , but patients who received asct did not show significant differences in survival ( p=.221 , p=.323 , and p=.343 , respectively ) ( fig .
2 ) . when we stratified patients according to age , sex , and iss , low alc was associated with poor os in patients who were < 65 years - old ( p=.009 ) ,
high amc was associated with poor survival in the iss stage i group ( p<.0001 ) .
low alc / amc ratio was associated with poor survival in patients who were < 65 years - old ( p=.008 ) , male ( p=.018 ) , or had iss stage i ( p=.017 ) or stage iii disease ( p=.010 ) ( table 4 ) .
the aim of the present study was to investigate the role of amc as a prognostic biomarker for mm and to determine its relationship with alc , an established prognostic factor for mm .
to our knowledge , this is the first study to demonstrate the prognostic value of amc and the alc / amc ratio in newly diagnosed mm .
low alc ( < 1,400 cells/l ) , high amc ( 490 cells/l ) , and low alc / amc ratio ( < 2.9 ) were associated with poor os and poor prognostic factors such as high iss stage , plasmablastic morphology , hypoalbuminemia , and high 2 m . however , on multivariate analysis , only low alc / amc ratio was an independent prognostic factor for mm . although alc did not have statistical significance in multivariate analysis due to the relatively small sample size , our results are in agreement with previous reports showing that a high alc is associated with better prognosis in newly diagnosed mm ( cut - off point , 1,400 cells/l ; the same as that used our study),3 relapsed mm after vel - dex therapy ( cut - off point , 1,100 cells/l)23 and other lymphomas.24 we also found that shorter os in mm patients was associated with high amc and low alc / amc ratio , which is similar to the findings of previous studies of malignant lymphomas .
amc has been shown to be a reliable prognostic marker for dlbcl ( cut - off point , 630 cells/l),16 fl ( cut - off point , 570 cells/l),17 and hl ( cut - off point , 900 cells/l),18 and in classical hl , the alc / amc ratio at diagnosis is an independent prognostic factor for survival ( cut - off point , 1.1).18 recently it has been reported that tams are a prognostic marker for the survival of patients with mm.13 tams , which constitute a significant proportion of tumor - infiltrating inflammatory cells , have been linked to the growth , angiogenesis and metastasis of a variety of cancers.7 in mm , macrophages are an abundant and important component of bm stromal cells and contribute to tumor angiogenesis.25,26 tams , which are continually being recruited and activated both in an autocrine manner and by cytokines secreted by myeloma cells , adapt functionally , phenotypically and morphologically to collaborate with endothelial cells in vessel formation.27 moreover , bm macrophages protect myeloma cells from apoptosis.28 tams therefore promote tumor growth not only by supporting angiogenesis , but also by protecting tumor cells from apoptosis , via the induction of immunosuppression.29 the important role tams play in the biology of mm , thereby affecting patient outcome , makes them a potential target for anti - vascular therapy in mm.26 as tams are derived from circulating monocytes and are recruited to the tumor site by tumor - derived chemotactic factors,14,15,30 obtaining an amc from a cbc at diagnosis is simple and could be more easily applied in clinical practice than counting tams . in this study ,
moreover , the alc / amc ratio , which may be a reflection of both the tumor microenvironment and host immune status , could provide prognostic information independently .
we found that the patient group with high amc and low alc / amc ratio trended toward worse os whether or not they received asct , although statistical significance was not reached in the asct group because of the small sample size . a larger prospective cohort study of uniformly treated patients is required to validate these findings . in conclusion
, the results of the present study suggest that amc , and , in particular , alc / amc ratio , which was found to be an independent prognostic factor for patient survival , could be used to determine the prognosis of mm .
 backgroundabsolute lymphocyte count ( alc ) in peripheral blood has recently been reported to be an independent prognostic factor in multiple myeloma ( mm ) . 
 previous studies indicated that the absolute monocyte count ( amc ) in peripheral blood reflects the state of the tumor microenvironment in lymphomas . 
 neither the utility of the amc nor its relationship with alc has been studied in mm.methodsthe prognostic value of alc , amc , and the alc / amc ratio at the time of diagnosis was retrospectively examined in 189 patients with mm.resultson univariate analysis , low alc ( < 1,400 cells/l ) , high amc ( 490 cells/l ) , and low alc / amc ratio ( < 2.9 ) were correlated with worse overall survival ( os ) ( p=.002 , p=.038 , and p=.001 , respectively ) . 
 on multivariate analysis , the alc / amc ratio was an independent prognostic factor ( p=.047 ) , whereas alc and amc were no longer statistical significant . 
 low alc , high amc , and low alc / amc ratio were associated with poor prognostic factors such as high international staging system stage , plasmablastic morphology , hypoalbuminemia , and high 2-microglobulin.conclusionsunivariate analysis demonstrated that changes in alc , amc , and the alc / amc ratio are associated with patient survival in mm . 
 multivariate analysis showed that , of these factors , the alc / amc ratio was an independent prognostic factor for os . 
MATERIALS AND METHODS
Patients
Statistical analysis
Ethical permission
RESULTS
Patient characteristics
Correlation of ALC, AMC, and the ALC/AMC ratio with clinicopathological variables
Prognostic significance of ALC, AMC, and the ALC/AMC ratio
DISCUSSION