The Diagnostic Value Of Using ¹⁸F-Fluorodeoxyglucose Positron Emission Tomography To Differentiate Between Low- And High-Grade Meningioma

Figures & data

Table 1 Clinical Features Of Enrolled Patients

Characteristics		Number
Mean age		58.8 ± 10.8 years
Gender
	Male	45 (36.3%)
Female	79 (63.7%)
Tumor grade
Grade I (n = 98)	Meningethelial	32 (25.7%)
	Fibrous	40 (32.3%)
	Angiomatous	5 (4.0%)
	Microcystic	3 (2.4%)
	Psammomatous	4 (3.2%)
	Secretory	8 (6.5%)
	Transitional	5 (4.0%)
Metaplastic	1 (0.8%)
Grade II (n = 13)	Atypical	7 (5.6%)
	Clear cell	2 (1.6%)
Chordoid	4 (3.2%)
Grade III (n = 13)	Anaplastic	7 (5.6%)
	Rhabdoid	4 (3.2%)
Papillary	2 (1.6%)
Tumor location	Non-skull base	72 (58.1%)
Skull base	52 (41.9%)
Recurrent meningioma		17 (13.7%)
Preoperative KPS		89.8 ± 6.0 (range, 70–100)
Ki-67 labeling index		4.0% ± 5.4% (range 1% - 25%)
TGR of FDG uptake
	Tumor to contralateral cerebral	1.2 ± 1.2 (range 0.3–9.0)
Tumor to ipsilateral cerebellum	1.1 ± 1.1 (range 0.3–10.3)

Abbreviations: KPS, Karnofsky performance scale; TGR, tumor to grey ratio; FDG, fluorodeoxyglucose.

Figure 1 Analysis of meningioma patients using 18F-FDG PET from the database.

Table 2 Comparison Of Characteristics Of Patients By Different WHO Grades (Grade I Vs Grade II Vs Grade III)

Characteristics	WHO Grade I (n=98)	WHO Grade II (n=13)	WHO Grade III (n=13)	P value
Mean age (years)	58.2 ± 1.2 (95% CI:55.8–60.5)	59.5 ± 3.2 (95% CI: 52.4–66.5)	60.8 ± 3.0 (95% CI:54.2–67.5)	0.6009^a
TGR of FDG uptake	0.9 ± 0.8 (95% CI:0.8–1.1)	1.6 ± 0.2 (95% CI: 1. 2–1.9)	2.0 ± 2.3 (95% CI: 0.6–3.4)	0.0001^a
Ki-67 labeling index	1.5 ± 0.8 (95% CI:1.3–1.7)	11.8±7.2 (95% CI: 8.9–14.7)	15.0 ± 1.5 (95% CI: 11.7–18.3)	0.0001^a
Tumor location (non-skull base/skull base)	55/43	8/5	9/4	0.725^b

Notes: ^aKruskal–Wallis test; ^bFisher’s exact test.

Figure 2 Scatter plot showing the association between the TGR on FDG PET and the tumor proliferative behavior (Ki-67 labeling index).

Figure 3 ROC curve of the TGR of meningioma. AUC of the TGR between low grade (WHO grade I) and high grade (WHO grade II&III) was 0.8533. The optimal cut-off value was 1.30. The sensitivity and specificity were 69.23% and 91.84%, respectively.

Table 3 Univariate And Multivariate Analysis Of Prognostic Factors In Patients With Meningioma In Our Series

Variable	Univariate Analysis		Multivariate Analysis
	PFS		PFS
p	HR (95% CI)	p	HR (95% CI)
Age (<60/≥60)	0.716	1.24 (0.39–3.90)
Gender (male/female)	0.399	0.57 (0.15–2.11)
Preoperative KPS (<80/≥80)	0.612	1.70 (0.22–13.19)
Extent of resection (GTR/STR)	0.982	1.02 (0.27–3.76)
Location (skull base/non-skull base)	0.118	3.36 (0.73–15.33)
Ki-67 index (<5%/≥5%)	0.001*	9.88 (2.67–36.52)
TGR (<1.30/≥1.30)	0.000*	17.46 (3.82–79.76)	0.013*	9.63 (1.62–57.17)
Treatment status (newly diagnosed/recurrent)	0.048*	2.37 (1.01–11.24)
Tumor grade(grade I vs grade II&III)	0.001*	7.64 (2.30–25.42)

Note: *P<0.05 considered statistically significant.

Abbreviations: KPS, Karnofsky performance score; PFS, progression-free survival; HR, hazard ratio; CI, confidence interval; GTR, gross total resection; STR, subtotal resection; TGR, tumor to grey ratio.

Figure 4 Kaplan-Meier survival curve. Progression-free survival of patients by TGR (<1.30 vs ≥1.30).