Patient Characteristics
The demographics and baseline characteristics of the 216 patients were presented in Table 1. In this study, all patients were divided into a recurrence group (n = 77, 35.60%) and a non-recurrence group (n = 139, 64.40%). Overall, the average age of patients was 43.58 ± 17.22 years old; 53.7% (116 of 216) of the enrolled patients were male and 46.30% of them were female. Age, leukocyte count, neutrophil count, lymphocyte count, NLR, LMR, serum sodium level, serum potassium level, serum LDH level, World Health Organization (WHO) grade were significantly different between the two groups. The difference of Karnofsky Performance Status (KPS) for the two groups was not significant, P = 0.057.
Table 1
Comparison of Demographic and Clinical Variables in Patients with PFS < 1 and PFS ≥ 1
Parameter
|
Total
|
Recurrence group(n = 77)
|
Non-recurrence group(n = 139)
|
P value
|
Age
|
43.58 ± 17.22
|
47.88 ± 19.12
|
41.20 ± 15.65
|
0.006
|
KPS score
|
80(70–90)
|
80(70–90)
|
80(70–90)
|
0.057
|
Sex
|
|
|
|
0.299
|
Male
|
116(53.7%)
|
45(58.4%)
|
71(51.1%)
|
|
Female
|
100(46.3%)
|
32(41.6%)
|
68(48.9%)
|
|
Hypertension
|
|
|
|
0.587
|
No
|
194(89.8%)
|
68(88.3%)
|
126(90.6%)
|
|
Yes
|
22(10.2%)
|
9(11.7%)
|
13(9.4%)
|
|
Diabetes mellitus
|
|
|
|
0.693
|
No
|
209(96.8%)
|
74(96.1%)
|
135(97.1%)
|
|
Yes
|
7(3.2%)
|
3(3.9%)
|
4(2.9%)
|
|
WBC count 10^9/L
|
7.51 ± 2.96
|
8.35 ± 3.42
|
7.06 ± 2.57
|
0.005
|
RBC count 10^12/L
|
4.65 ± 0.48
|
4.64 ± 0.46
|
4.65 ± 0.50
|
0.896
|
NEU count 10^9/L
|
5.02 ± 2.92
|
6.06 ± 3.53
|
4.45 ± 2.34
|
0.001
|
MON count 10^9/L
|
0.41 ± 0.19
|
0.43 ± 0.18
|
0.40 ± 0.19
|
0.366
|
LYM count 10^9/L
|
1.81 ± 0.70
|
1.62 ± 0.74
|
1.91 ± 0.65
|
0.003
|
PLT count 10^9/L
|
234.29 ± 62.70
|
239.35 ± 63.25
|
231.49 ± 62.45
|
0.379
|
NLR
|
3.94 ± 5.92
|
5.34 ± 6.01
|
3.16 ± 5.75
|
0.011
|
PLR
|
159.98 ± 145.63
|
180.97 ± 105.08
|
148.35 ± 163.02
|
0.115
|
LMR
|
4.98 ± 2.29
|
4.22 ± 2.03
|
5.40 ± 2.33
|
< 0.001
|
HGB g/L
|
138.26 ± 16.42
|
139.43 ± 14.13
|
137.61 ± 17.58
|
0.437
|
Serum glucose mmol/L
|
5.25 ± 1.57
|
5.48 ± 1.99
|
5.13 ± 1.28
|
0.158
|
Serum sodium mmol/L
|
140.95 ± 2.94
|
140.28 ± 3.35
|
141.33 ± 2.62
|
0.011
|
Serum potassium mmol/L
|
4.18 ± 0.42
|
4.09 ± 0.43
|
4.23 ± 0.41
|
0.018
|
Serum calcicum mmol/L
|
2.28 ± 0.15
|
2.29 ± 0.18
|
2.28 ± 0.12
|
0.462
|
Preoperative LDH U/L
|
181.07 ± 59.08
|
215.23 ± 81.40
|
162.15 ± 27.90
|
< 0.001
|
Postoperative LDH U/L
|
223.41 ± 90.66
|
255.24 ± 81.85
|
205.77 ± 90.99
|
0.005
|
ΔLDH U/L
|
43.28 ± 87.93
|
31.56 ± 81.85
|
49.77 ± 88.21
|
0.289
|
Tumor volume cm³
|
39.76 ± 38.94
|
44.36 ± 39.86
|
37.22 ± 38.33
|
0.198
|
Peritumor edema cm
|
2.10 ± 1.23
|
2.27 ± 1.10
|
2.01 ± 1.30
|
0.149
|
CCRT
|
|
|
|
0.355
|
No
|
70(32.4%)
|
28(36.4%)
|
42(30.2%)
|
|
Yes
|
146(67.6%)
|
49(63.6%)
|
97(69.8%)
|
|
Surgical therapy
|
|
|
|
0.972
|
GTR
|
155(71.8%)
|
56(72.7%)
|
99(71.2%)
|
|
STR
|
58(26.9%)
|
20(26.0%)
|
38(27.3%)
|
|
biopsy
|
3(1.4%)
|
1(1.3%)
|
2(1.4%)
|
|
WHO grade
|
|
|
|
< 0.001
|
I
|
32(14.8%)
|
3(3.9%)
|
29(20.9%)
|
|
II
|
53(24.5%)
|
5(6.5%)
|
48(34.5%)
|
|
III
|
34(15.7%)
|
4(5.2%)
|
30(21.6%)
|
|
IV
|
97(44.9%)
|
65(84.4%)
|
32(23.0%)
|
|
Values are reported as number, number(%), mean ± standard deviation, and median (25%–75%). |
PFS, progression-free survival; KPS, karnofsky performance status; WBC, white blood cell; RBC, red blood cell; NEU, neutrophil; MON, monocyte; LYM, lymphocyte; PLT, platelet; NLR, neutrophil-lymphocyte ratio; PLR, platelet-to-lymphocyte ratio; LMR, lymphocyte–monocyte ratio; HGB, hemoglobin; LDH, Lactate dehydrogenase; CCRT, concurrent chemoradiotherapy; GTR, gross total resection; STR, subtotal resection; WHO, World Health Organization. |
There were 115 patients underwent postoperative reexamination for the serum LDH level. The postoperative serum LDH level was significantly higher than preoperative serum LDH level, 223.41 ± 90.66 vs 181.07 ± 59.08, P<0.001. The postoperative serum LDH level in recurrence group was significantly higher than that in non-recurrence group, P = 0.005. There was no significant difference in ΔLDH between the two groups, P = 0.289.
Association between LDH and Tumor Recurrence within 1 Year after Surgery in Glioma Patients
Factors with significant univariate association (P < 0.10) for 1-year PFS were all shown in Table 2, including age, KPS score, white blood cell count, neutrophil count, lymphocyte count, NLR, LMR, serum sodium level, serum potassium level, serum LDH level, WHO grade. After multivariate analysis, only serum LDH level (odds ratio [OR] = 0.97, 95% confidence interval [CI] = 0.96–0.98, P<0.001) and WHO grade (grade II: OR = 19.64, 95%CI = 5.56–69.35, P<0.001; grade III: OR = 19.50, 95%CI = 7.08–53.73, P<0.001; grade IV: OR = 15.23, 95%CI = 4.94–46.97, P<0.001) were still significant and independent of 1-year PFS after adjusting for confounders.
Table 2
Univariate and Multivariate Analysis of 1-year PFS with Possible Predictive Factors
Parameter
|
Univariate analysis
|
Multivariate analysis
|
OR
|
95% CI
|
P value
|
OR
|
95% CI
|
P value
|
Age
|
0.98
|
0.96–0.99
|
0.007
|
|
|
|
KPS score
|
1.03
|
1.00-1.06
|
0.067
|
|
|
|
WBC count 10^9/L
|
0.86
|
0.78–0.95
|
0.004
|
|
|
|
NEU count 10^9/L
|
0.82
|
0.74–0.91
|
< 0.001
|
|
|
|
LYM count 10^9/L
|
1.90
|
1.23–2.95
|
0.004
|
|
|
|
NLR
|
0.92
|
0.85–0.99
|
0.029
|
|
|
|
LMR
|
1.31
|
1.12–1.53
|
< 0.001
|
|
|
|
Serum sodium mmol/L
|
1.13
|
1.03–1.25
|
0.014
|
|
|
|
Serum potassium mmol/L
|
2.30
|
1.14–4.63
|
0.020
|
|
|
|
LDH U/L
|
0.97
|
0.96–0.98
|
< 0.001
|
0.97
|
0.96–0.98
|
< 0.001
|
WHO grade
|
|
|
< 0.001
|
|
|
< 0.001
|
I
|
1.00
|
Reference
|
|
1.00
|
Reference
|
|
II
|
19.64
|
5.56–69.35
|
< 0.001
|
24.22
|
5.95–98.58
|
< 0.001
|
III
|
19.50
|
7.08–53.73
|
< 0.001
|
39.81
|
10.62-149.25
|
< 0.001
|
IV
|
15.23
|
4.94–46.97
|
< 0.001
|
28.82
|
6.22-133.61
|
< 0.001
|
PFS, progression-free survival; OR: odds ratio; CI: confidence interval; WBC, white blood cell; NEU, neutrophil; LYM, lymphocyte; NLR, neutrophil-lymphocyte ratio; LMR, lymphocyte–monocyte ratio; LDH, Lactate dehydrogenase; WHO, World Health Organization. |
Utilizing ROC analysis, the prognostic value of preoperative LDH level and WHO grade were presented in Fig. 1. The best cut-off value of preoperative LDH level for predicting 1-year PFS was 179 U/L. The predictive performance was represented with AUC = 0.741 (95%CI = 0.677–0.798), sensitivity = 74.8%, specificity = 63.6%, and Youden index = 0.385. Based on the best cut-off value of grade III, the predictive performance of WHO grade (AUC = 0.810, 95%CI = 0.751–0.860, sensitivity = 84.4%, specificity = 77.0%, and Youden index = 0.614) was also calculated by ROC analysis (Fig. 1). DeLong’s test indicated that the AUC of preoperative LDH level was comparable with that of WHO grade (Z = 1.363, P = 0.170).
In the WHO grade I-II group, the best cut-off value of preoperative LDH level for predicting 1-year PFS was 183.50 U/L. The predictive performance was represented by AUC = 0.934 (95%CI = 0.866-1.000), sensitivity = 100.0%, specificity = 74.0%, and Youden index = 0.740 (Figure 2A). In the WHO grade III-IV group (Figure 2B), the cut-off value was 177.50 U/L for preoperative LDH level (AUC = 0.733, 95%CI = 0.648–0.818, sensitivity = 60.9%, specificity = 80.6%, and Youden index = 0.415).
Univariate and Multivatiate Survival Analysis in Patients with and without Elevated Preoperative LDH at 2-year Follow-up
Based on the normal threshold of LDH level, patients was divided into normal LDH group (<250U/L) and elevated LDH group (>250U/L). In the Kaplan-Meier curves analysis, the 2-year survival rate was statistically correlated with the LDH level (P<0.001, Fig. 3). In normal LDH group and elevated LDH group, the 2-year survival rates were 61.3% (117/191) and 8.0% (2/25), respectively; the mean 2-year OS were 19.13 (95%CI = 18.10-20.16) and 10.44 (95%CI = 7.36–13.52), respectively. In the subgroup analysis based on WHO grade (low-grade group: grade I-II; high-grade group: grade III-IV), LDH level was still associated with 2-year survival rate. For patients in the low-grade group (Figure 4A), the 2-year survival rates in normal LDH group and elevated LDH group were 96.3% (77/80) and 0% (0/5), respectively (P<0.001). For the other patients in the high-grade group (Figure 4B), the 2-year survival rates in normal LDH group and elevated LDH group were 36.0% (40/111) and 10.0% (2/20), respectively (P = 0.001).
In the univariate Cox hazard regression analysis (Table 3), age (hazard ratio [HR] = 1.03, 95%CI = 1.01–1.04, P<0.001), white blood cell count (HR = 1.08, 95%CI = 1.03–1.14, P = 0.002), neutrophil count (HR = 1.12, 95%CI = 1.06–1.17, P<0.001), lymphocyte count (HR = 0.57, 95%CI = 0.42–0.78, P<0.001), NLR (HR = 1.02, 95%CI = 1.00-1.04, P = 0.016), LMR (HR = 0.84, 95%CI = 0.76–0.93, P = 0.001), serum glucose (HR = 1.16, 95%CI = 1.05–1.28, P = 0.003), serum sodium (HR = 0.93, 95%CI = 0.87–0.99, P = 0.027), serum potassium (HR = 0.65, 95%CI = 0.40–1.07, P = 0.089), LDH level (HR = 4.38, 95%CI = 2.73–7.04, P<0.001), and WHO grade (P<0.001) were all significantly associated with survival at 2-year follow-up. Furthermore, multivariate Cox analysis revealed that LDH level (HR = 2.56, 95%CI = 1.59–4.15, P<0.001) and WHO grade (grade II: HR = 4.58, 95%CI = 0.56–37.23, P = 0.155; grade III: HR = 16.35, 95%CI = 2.16–123.80, P = 0.007; grade IV: HR = 42.13, 95%CI = 5.83-304.47, P<0.001) remained associated with survival at 2-year follow-up (Table 3).
Table 3
Univariate and Multivariate Cox Hazard Regression Analysis of 2-year OS with Possible Predictive Factors
Parameter
|
Univariate analysis
|
Multivariate analysis
|
HR
|
95% CI
|
P value
|
HR
|
95% CI
|
P value
|
Age
|
1.03
|
1.01–1.04
|
< 0.001
|
|
|
|
WBC count 10^9/L
|
1.08
|
1.03–1.14
|
0.002
|
|
|
|
NEU count 10^9/L
|
1.12
|
1.06–1.17
|
< 0.001
|
|
|
|
LYM count 10^9/L
|
0.57
|
0.42–0.78
|
< 0.001
|
|
|
|
NLR
|
1.02
|
1.00-1.04
|
0.016
|
|
|
|
LMR
|
0.84
|
0.76–0.93
|
0.001
|
|
|
|
Serum glucose mmol/L
|
1.16
|
1.05–1.28
|
0.003
|
|
|
|
Serum sodium mmol/L
|
0.93
|
0.87–0.99
|
0.027
|
|
|
|
Serum potassium mmol/L
|
0.65
|
0.40–1.07
|
0.089
|
|
|
|
LDH level(normal or abnormally elevated)
|
4.38
|
2.73–7.04
|
< 0.001
|
2.56
|
1.59–4.15
|
< 0.001
|
WHO grade
|
|
|
< 0.001
|
|
|
< 0.001
|
I
|
1.00
|
Reference
|
|
1.00
|
Reference
|
|
II
|
4.55
|
0.56–36.95
|
0.157
|
4.58
|
0.56–37.23
|
0.155
|
III
|
16.41
|
2.17-124.24
|
0.007
|
16.35
|
2.16–123.80
|
0.007
|
IV
|
48.01
|
6.66-346.13
|
< 0.001
|
42.13
|
5.83-304.47
|
< 0.001
|
OS: overall survival; HR: hazard ratio; CI: confidence interval; WBC, white blood cell; NEU, neutrophil; LYM, lymphocyte; NLR, neutrophil-lymphocyte ratio; LMR, lymphocyte–monocyte ratio; LDH, Lactate dehydrogenase; WHO, World Health Organization. |
Univariate and Multivatiate Survival Analysis in Patients with and without Elevated Preoperative LDH at 3-year Follow-up
In the Kaplan-Meier curves analysis, the 3-year survival rate was statistically associated with the LDH level (P<0.001, Fig. 5). In normal LDH group and elevated LDH group, the 3-year survival rates were 49.2% (94/191) and 0% (0/25), respectively; the mean 3-year OS were 25.45 (95%CI = 23.72–27.18) and 10.82 (95%CI = 7.38–14.26), respectively. In the subgroup analysis based on WHO grade, LDH level was still associated with 3-year survival rate. For patients in the low-grade group (Figure 6A), the 3-year survival rates in normal LDH group and elevated LDH group were 90.0% (72/80) and 0% (0/5), respectively (P<0.001). For the other patients in the high-grade group (Figure 6B), the 3-year survival rates in normal LDH group and elevated LDH group were 19.8% (22/111) and 0% (0/20), respectively (P = 0.001).
In the univariate Cox hazard regression analysis (Table 4), age (HR = 1.03, 95%CI = 1.02–1.05, P<0.001), white blood cell count (HR = 1.10, 95%CI = 1.05–1.15, P<0.001), neutrophil count (HR = 1.14, 95%CI = 1.09–1.19, P<0.001), lymphocyte count (HR = 0.51, 95%CI = 0.39–0.68, P<0.001), NLR (HR = 1.03, 95%CI = 1.02–1.05, P<0.001), LMR (HR = 0.87, 95%CI = 0.79–0.95, P = 0.002), serum glucose (HR = 1.20, 95%CI = 1.10–1.30, P<0.001), serum sodium (HR = 0.93, 95%CI = 0.88-1.00, P = 0.029), LDH level (HR = 4.55, 95%CI = 2.89–7.16, P<0.001), and WHO grade (P<0.001) were all significantly correlated with survival at 3-year follow-up. Multivariate Cox analysis revealed that lymphocyte count (HR = 0.68, 95%CI = 0.51–0.91, P = 0.008), LDH level (HR = 2.21, 95%CI = 1.40–3.49, P = 0.001), and WHO grade (grade II: HR = 1.44, 95%CI = 0.44–4.68, P = 0.543; grade III: HR = 4.99, 95%CI = 1.68–14.87, P = 0.004; grade IV: HR = 16.96, 95%CI = 6.13–46.93, P<0.001) remained associated with survival at 3-year follow-up (Table 4).
Table 4
Univariate and Multivariate Cox Hazard Regression Analysis of 3-year OS with Possible Predictive Factors
Parameter
|
Univariate analysis
|
Multivariate analysis
|
HR
|
95% CI
|
P value
|
HR
|
95% CI
|
P value
|
Age
|
1.03
|
1.02–1.05
|
< 0.001
|
|
|
|
WBC count 10^9/L
|
1.10
|
1.05–1.15
|
< 0.001
|
|
|
|
NEU count 10^9/L
|
1.14
|
1.09–1.19
|
< 0.001
|
|
|
|
LYM count 10^9/L
|
0.51
|
0.39–0.68
|
< 0.001
|
0.68
|
0.51–0.91
|
0.008
|
NLR
|
1.03
|
1.02–1.05
|
< 0.001
|
|
|
|
LMR
|
0.87
|
0.79–0.95
|
0.002
|
|
|
|
Serum glucose mmol/L
|
1.20
|
1.10–1.30
|
< 0.001
|
|
|
|
Serum sodium mmol/L
|
0.93
|
0.88-1.00
|
0.029
|
|
|
|
LDH level(normal or abnormally elevated)
|
4.55
|
2.89–7.16
|
< 0.001
|
2.21
|
1.40–3.49
|
0.001
|
WHO grade
|
|
|
< 0.001
|
|
|
< 0.001
|
I
|
1.00
|
Reference
|
|
1.00
|
Reference
|
|
II
|
1.46
|
0.45–4.75
|
0.528
|
1.44
|
0.44–4.68
|
0.543
|
III
|
5.28
|
1.78–15.71
|
0.003
|
4.99
|
1.68–14.87
|
0.004
|
IV
|
20.61
|
7.51–56.58
|
< 0.001
|
16.96
|
6.13–46.93
|
< 0.001
|
OS: overall survival; HR: hazard ratio; CI: confidence interval; WBC, white blood cell; NEU, neutrophil; LYM, lymphocyte; NLR, neutrophil-lymphocyte ratio; LMR, lymphocyte–monocyte ratio; LDH, Lactate dehydrogenase; WHO, World Health Organization. |