Clinicopathological Characteristics
The current study included 50 patients (9 male and 41 female patients) with intracranial meningioma of various grades: 32 benign (GI) and 12 atypical (GII) and 6 anaplastic (GIII). In the group of benign meningiomas, 18 were meningothelial, 8 fibroblastic, 2 psammomatous, 2 microcystic and 2 angiomatous.
The patients’ age ranged from 17 – 67 years with a mean age of 50.22±12.56. For statistical purpose the studied cases were divided into two groups 32 benign (GI) meningiomas and 18 atypical and anaplastic meningiomas (GII/GIII).
Complete excision, including dura and bone (Simpson grade 1), had been performed in 10/50 meningiomas (20%). Complete excision plus apparently reliable coagulation of dural attachments (Simpson grade 2) had been gained in 36/50 cases (72%). Complete excision of the solid tumor, but with insufficient dural coagulation or bone excision (Simpson grade 3), had been performed in 2/50 cases (4%).Tumor biopsy (Simpson grade 4) had been gained in 2/50 (4%).
Four patients had died of their tumor during the follow-up period. The median OS of these patients was 4.9 years (range: 3.95-4.93) using Kaplan-Meier estimates. The clinical characteristics of the patients are listed in Table 1
Table (1) Clinical characteristics of patients with intracranial meningiomas:
Histological type
|
Number (%)
|
Age (mean±SD)
|
Sex (No/%)
|
Simpson grade
|
OS
|
Male
|
Female
|
I
|
II
|
III
|
IV
|
Alive
|
Dead
|
Benign (GI)
|
32
|
54.19±9.55
|
4(12.5)
|
28(87.5)
|
8(25.0)
|
22(8.8)
|
----
|
2(6.3)
|
32
|
0
|
Meningothelial
|
18(36.0)
|
55.67±9
|
2 (22.2)
|
16 (39.0)
|
6 (60.0 )
|
12 (33.3)
|
----
|
0.0
|
|
|
Fibroblastic
|
8(16.0)
|
53.25±10.38
|
2 (22.2)
|
6 ( 14.6)
|
2 (20.0)
|
4 (11.1)
|
-----
|
2(100.0)
|
|
|
Microcystic
|
2 (4.0)
|
45±0
|
0 (0.0)
|
2 ( 4.9)
|
0.0
|
2 (5.6)
|
------
|
0.0
|
|
|
Psammomatous
|
2(4.0)
|
65±0
|
0 (0.0)
|
2 (4.9)
|
0.0
|
2 (5.6)
|
------
|
0.0
|
|
|
Angiomatous
|
2(4.0)
|
43±0
|
0 (0.0)
|
2 (4.9)
|
0.0
|
2 (5.6)
|
------
|
0.0
|
|
|
Atypical (GII)
|
12
|
38.5±15.17
|
2(16.7)
|
10(83.3)
|
2 (20.0)
|
8 (22.2)
|
2(100.0)
|
0.0
|
10
|
2
|
Anaplastic (GIII)
|
6 (12%)
|
52.5±6.02
|
3(50.0)
|
3(50.0)
|
0 (0.0)
|
6 (16.7)
|
0(0.0)
|
0.0
|
4
|
2
|
Association between immunohistochemical markers and clinicopathological parameter.
All cases of meningiomas express the CD44 (Cytoplasmic and/or membranous), cytoplasmic MMP-9 and nuclear Ki-67.
CD44 expression:
The mean of CD44 score was 3.38±0.87 of benign (GI) and 4.67 ± 0.8 for atypical and anaplastic meningiomas (GII/III). There was significant association between CD44scores and different grades (I vs II/III; Figuer1A-C) of meningiomas (p= <0.001) and Simpson grade (p=0.026). Table2
Table 2: Summary of Clinicopathological Data of Meningioma Patients
Parameter
|
No.
|
CD44
|
MMP-9
|
Ki-67%
|
Mean ± SD
|
Median (IQR)
|
P-value
|
Mean ± SD
|
Median (IQR)
|
P-value
|
Mean ± SD
|
Median (IQR)
|
P-value
|
Age Group
|
|
|
|
|
|
|
|
|
|
|
|
24
|
3.83 ± 1.1
|
4 (2)
|
= 0.935
|
4.50 ± 1.6
|
5 (3)
|
= 0.261
|
8.45 ± 7.9
|
6 (5)
|
= 0.115
|
|
26
|
3.85 ± 1.1
|
4 (1)
|
4.04 ± 1.6
|
4 (2)
|
5.51 ± 4.8
|
4 (4)
|
Sex
|
|
|
|
|
|
|
|
|
|
|
|
41
|
3.80 ± 1.1
|
4 (2)
|
= 0.356
|
4.20 ± 1.5
|
5 (3)
|
= 0.402
|
6.55 ± 6.2
|
5 (5)
|
= 0.026
|
|
9
|
4.00 ± 0.7
|
4 (1)
|
4.56 ± 1.9
|
5 (2)
|
8.60 ± 6.1
|
13 (11)
|
Grade
|
|
|
|
|
|
|
|
|
|
|
|
32
|
3.38 ± 0.9
|
3 (1)
|
< 0.001
|
3.81 ± 1.5
|
4 (2)
|
< 0.001
|
3.28 ± 2.2
|
3 (3)
|
< 0.001
|
|
18
|
4.67 ± 0.8
|
4 (1)
|
5.06 ± 1.4
|
5.5 (1)
|
13.89 ± 6.8
|
14 (10)
|
Simpson Grade
|
|
|
|
|
|
|
|
|
|
|
|
10
|
3.40 ± 1.4
|
3 (1)
|
=0.026**
|
3.80 ± 1.9
|
3.5 (2)
|
= 0.527
|
7.80 ± 6.7
|
3 (3)
|
= 0.845
|
|
36
|
3.89 ± 1.0
|
4 (1)
|
4.42 ± 1.5
|
5 (3)
|
6.58 ± 5.4
|
6 (5.5)
|
|
4
|
4.50 ± 0.6
|
4.5 (1)
|
4.00 ± 1.2
|
4 (2)
|
7.80 ± 5.2
|
8 (7)
|
Expression pattern of CD44 (Cytoplasmic and/or membranous) was evaluated in all studied meningiomas. Within those with of benign (GI) meningiomas 20/32 (62.5%) express the membranous pattern, however 10/12 (83.3%) and 6/6 of atypical and anaplastic express the membranous pattern, respectively (Figure 2 A&B). The differences in the expression pattern between different grades of meningiomas were statistically significant (P= <0.001). The details of expression pattern of CD44 are listed in Table 3.
Table 3: The CD44 protein expression patterns in intracranial meningiomas.
|
Types
|
P. value
|
Benign (n=32)
|
Atypical (n=12)
|
Anaplastic (n=6)
|
|
|
|
|
|
CD44C*
|
|
|
|
|
|
|
|
-
|
0
|
0.0
|
0
|
0.0
|
3
|
50.0
|
<0.001**
|
+
|
16
|
50.0
|
2
|
16.7
|
0
|
0.0
|
++
|
4
|
12.5
|
2
|
16.7
|
3
|
50.0
|
+++
|
12
|
37.5
|
8
|
66.7
|
0
|
0.0
|
CD44M*
|
|
|
|
|
|
|
|
-
|
12
|
37.5
|
2
|
16.7
|
0
|
0.0
|
<0.001**
|
+
|
14
|
43.8
|
8
|
66.7
|
0
|
0.0
|
++
|
6
|
18.8
|
2
|
16.7
|
3
|
50.0
|
+++
|
0
|
0.0
|
0
|
0.0
|
3
|
50.0
|
MMP-9 expression;
The mean of MMP-9 score of benign (GI) meningiomas were 3.81 ± 1.5, while atypical and anaplastic meningiomas (GII/III) were 5.06 ± 1.4. There was significant association between MMP-9 scores and pathological grades of meningiomas (P< 0.001; Figure 1 D-F). There was no significant correlation between MMP-9 and other clinicopathological variables (Table 2).
Ki-67 Expression;
The mean of Ki67 score within benign meningiomas (GI) were 3.28 ± 2.2, of atypical and anaplastic meningiomas (GII/III) was 12.08%±8%. Ki67 expression showed significant association with meningiomas grade (P<0.001; Figure 1 G-I) and gender (p=0.026). (Table2)
Correlation between the immunohistochemical markers:
Significant positive correlation was noted between Ki-67 and CD44 score, Ki-67 and MMP-9, CD44 membranous expression and MMP-9 (r=0.263, p =0.032), (r=0.256 p=0.037), (r=0.572, p= <0.001), respectively. Interestingly, however there was negative correlation between MMP9 and CD44 score (r= -0.035 p=0.405), there was positive correlation between MMP9 and CD44 membranous expression (r=0.242, p=0.045). The details of Spearman’s correlation between immunohistochemical markers are listed in Table 4.
Table 4: The correlation among the expression values of Ki67, CD44, and MMP9 protein expression in intracranial meningiomas.
Parameter
|
Ki67
|
MMP9
|
CD44 Score
|
rho* (P-value)
|
Total (n=50)
|
|
0.263 (=0.032)
|
-0.035 (=0.405)
|
1
|
|
0.036 (=0.402)
|
-0.257 (=0.036)
|
1
|
|
0.572 (<0.001)
|
0.242 (=0.045)
|
1
|
|
0.256 (=0.037)
|
1
|
-0.035 (=0.405)
|
*Spearman's Ranked Correlation Coefficient.
Survival Analyses
Overall survivals were analyzed by the expression of each immunohistochemical markers, age, gender, tumor grade and Simpson grade (II-IV). On univariate analysis , significant correlation was found between OS and age group (≥ 50 years), gender (male) and Grade II/III (p=0.041,p=0.012,p=0.014) respectively.
The expression of immunohistochemical markers (CD44 and MMP9) did not correlate with OS, however Ki67 showed statistically significant correlation with OS (OS: HR, 1.136 95% confidence interval (CI) 1.025-1.259, p=0.015).
On multivariate analysis, still age, GII/III and Ki-67 significantly correlated with OS (p= 0.046, p= 0.047, p= 0.048), respectively. Additionally, CD44 score and CD44 cytoplasmic was associated with poor OS (OS: HR, 1.881 95% confidence interval (CI) 1.121-4.123, p= 0.044) (OS: HR, 2.401 95% confidence interval (CI), 1.095-5.446, p= 0.046) respectively. The details of univariate correlation and multivariate analysis are listed in Table 5.
Table 5: Cox Proportional Hazard Regression analysis for overall survival in patients with intracranial meningiomas.
Variable
|
Univariate
|
Multivariate
|
HR (95% CI) *
|
P-value
|
HR (95% CI)
|
P-value
|
Age Group (≥ 50 years)
|
1.784 (1.024-2.927)
|
= 0.041
|
1.143 (1.011-3.154)
|
= 0.046
|
Sex (Male)
|
4.713 (1.664-8.479)
|
= 0.012
|
|
|
Grade (GII-III)
|
5.725 (1.422-9.046)
|
= 0.014
|
3.197 (1.055-6.201)
|
= 0.047
|
Ki67%
|
1.136 (1.025-1.259)
|
= 0.015
|
1.095 (1.025-1.259)
|
= 0.048
|
CD44 score
|
1.765 (0.723-4.306)
|
= 0.212
|
1.881 (1.121-4.123)
|
= 0.044
|
CD44 (Cytoplasmic)
|
1.993 (0.591-6.728)
|
= 0.266
|
2.401 (1.095-5.446)
|
= 0.046
|
CD44 (Membranous)
|
1.758 (0.612-5.051)
|
= 0.294
|
1.212 (0.702-7.811)
|
= 0.425
|
MMP9
|
1.471 (0.661-3.272)
|
= 0.344
|
|
|
Simpson Grade II-IV
|
1.209 (0.488-5.085)
|
= 0.495
|
|
|
OS: overall survival. *HR, Hazard Ratio; CI, Confidence Interval
According to Kaplan-Meier curve showed significant correlation between median OS and age (≥ 50 years; P=0.031), histological grade (GII/III; p=0.005), and nearly significant for Ki-67 (≥4 cutoff point; p=0.068). Interestingly, CD44 cytoplasmic revealed poor OS (p=0.048), however no association was found between median survival and CD44 membranous (Figure 4).