The value of contrast-enhanced harmonic endoscopic ultrasound in differential diagnosis and evaluation of malignant risk of gastrointestinal stromal tumors (<50mm)

Figures & data

Figure 1. Flow chart of patients enrolled.

Table 1. Clinical characteristics between leiomyoma and GISTs.

Characteristic	Total (n = 48)	Leiomyoma (n = 10)	GISTs (n = 38)	t/X2	p Value
Gender (Male vs Female)	25 (52.1%) vs 23 (47.9%)	6 (60%) vs 4 (40%)	19 (50.0%) vs 19 (50.0%)	0.043	0.836
Age, years (range)	58.3 (±10.56)	54.8 (±10.29)	59.8 (±10.31)	–1.355	0.182
Standard B-mode EUS findings
Size, mm (range)	27.3 (±13.34)	20.6 (±12.09)	30.0 (±13.23)	–1.843	0.072
LSR	1.3 (±0.36)	1.4 (±0.40)	1.2 (±0.34)	1.663	0.103
Tumor location				25.044	<0.001
Esophagus	6 (12.5%)	6 (60%)	0
Stomach	40 (83.3%)	3 (30%)	37 (97.4%)
Duodenum	2 (4.2%)	1 (10%)	1 (2.6%)
Origin layer					0.007*
Laminae muscularis mucosae	3 (6.3%)	3 (30%)	0
Muscularis propria	45 (93.7%)	7 (70%)	38 (100%)
Calcification (absent vs present)	42 (87.5%) vs 6 (12.5%)	10 (100%) vs 0	32 (84.2%) vs 6 (15.8%)		0.32*
Necrosis (absent vs present)	34 (70.8%) vs 14 (29.2%)	9 (90%) vs 1 (10%)	25 (65.8%) vs 13 (34.2%)		0.268*
CDFI (poor vs rich)	24 (50%) vs 24 (50%)	9 (90%) vs 1 (10%)	15 (39.5%) vs 23 (60.5%)	8.084	0.004
CEH-EUS findings
Arterial phase				25.700	<0.001
No-enhancement	3 (6.3%)	3 (30%)	0
Hypo-enhancement	9 (18.7%)	5 (50%)	3 (10.5%)
Iso-enhancement	2 (4.2%)	1 (10%)	2 (2.6%)
Hyper-enhancement	34 (70.8%)	1 (10%)	33 (86.9%)
Diffuse-enhancement				16.842	<0.001
No	12 (25%)	8 (80%)	4 (10.5%)
Yes	36 (75%)	2 (20%)	34 (89.5%)
Capsule enhancement (weak vs obvious)	9 (18.7%) vs 30 (81.3%)	8 (80%) vs 2 (20%)	1 (2.6%) vs 37 (97.4%)	26.235	<0.001
non-enhancing spots (absent vs present)	33 (68.8%) vs 15 (31.2%)	10 (100%) vs 0	23 (60.5%) vs 15 (39.5%)		0.02*

LSR: the long-to-short ratio; CDFI: Color Doppler Flow Imaging. *used Fisher’s exact test.

Figure 2. Under CEH-EUS, the enhancement signal in the tumor was lower than that in the surrounding normal tissues and the enhancement of the tumor capsule was slightly weaker. Postoperative pathology was diagnosed as leiomyoma.

Figure 3. Under CEH-EUS, the enhancement signal in the tumor was stronger than that in the surrounding normal tissues and the enhancement of the tumor capsule was obviously enhanced. Postoperative pathology was diagnosed as GIST.

Table 2. Comparison of the diagnostic value of CEH-EUS and consistency tests.

	Sensitivity	specificity	accuracy	PPV	NPV	McNeman	Kappa
CDFI	60.52%	90%	66.67%	95.83%	37.5%
Hyper-enhancement	86.84%	90%	87.50%	97.06%	64.29%	0.013^a	0.417^a
Diffuse-enhancement	89.47%	80%	87.50%	94.44%	66.67%	0.002^b	0.417^b
Capsule enhancement	97.37%	80%	93.75%	94.87%	88.89%	<0.001^c	0.292^c

PPV: positive predictive value; NPV: negative predictive value; ^ais a paired chi-square and consistency test between CDFI and hyper-enhancement, ^bis a paired chi-square and consistency test between CDFI and diffuse-enhancement, ^cis a paired chi-square and consistency test between CDFI and capsule enhancement.

Figure 4. Receiver-operating characteristic curve for the Signal appearance time (Area under the curve [AUC], 0.903).

Table 3. Arterial phase manifestations of GISTs at different risk levels.

	Very low risk GISTs(n = 6)	Low risk GISTs(n = 19)	Intermediate risk GISTs(n = 10)	High risk GISTs(n = 3)
Hypo-enhancement	3	0	0	0
Iso-enhancement	1	1	0	0
Hyper-enhancement	2	18	10	3

Table 4. Characteristics of very low-low risk GISTs and intermediate-high risk GISTs.

	Very low-low risk GISTs (n = 25)	Intermediate-high risk  GISTs (n = 13)	p Value
Standard B-mode EUS findings
Irregular tumor shape	2 (8%)	4 (30.8%)	0.154
Surface mucosa			0.004
Erythema	2 (8%)	0
Ulceration	3 (12%)	8 (61.5%)
Necrosis (absent vs present)	20 (80%) vs 5 (20%)	5 (38.5%) vs 8 (61.5%)	0.028
CDFI (poor vs rich)	10 (40%) vs 15 (60%)	5 (38.5%) vs 8 (61.5%)	1.000
CEH-EUS findings
Signal appearance time,s	15.5 (±5.42)	5.1 (±3.40)	<0.001
Irregular vessels	4 (16%)	11 (84.6%)	<0.001
Vessel diameter,mm	1.13 (±0.25)	2.23 (±0.39)	<0.001
Hetergeneous perfusion	4 (16%)	12 (92.3%)	<0.001
Non-enhancing spots	4 (16%)	11 (84.6%)	<0.001
Ki-67	5.16 (±2.81)	7.69 (±4.15)	0.032

Figure 5. We saw hyper-enhancement within the tumor, but the enhancement is very heterogeneous and non-enhancing spots were visible, which was pathologically confirmed as GIST with a high-risk classification.

Figure 6. 10 s after contrast injection, we saw a continuous, irregular vessel of approximately 2 mm in diameter in the tumor, which was pathologically confirmed as GIST with an intermediate risk classification.

Table 5. Logistic regression model for independent predictors of GISTs.

	Univariate analysis		Multivariate analysis
	OR (95% CI)	p	OR (95% CI)	p
Irregular vessels	12.73 (4.55–183.18)	<0.001	3.99 (1.04–90.95)	0.046
Hetergeneous perfusion	12.43 (6.30–630.41)	<0.001	2.27 (0.44–569.96)	0.132
Non-enhancing spots	12.73 (4.55–183.18)	<0.001	0.18 (0.07–57.08)	0.669

OR: odds ratio; CI: confidence interval.