Exploration of a new method for Photoshop-assisted endoscopic ultrasound to distinguish gastrointestinal stromal tumor and leiomyoma

Figures & data

Figure 1. Flow diagram describing the selection of the study population.

Figure 2. (A) EUS images of GIL, green arrow pointing to the tumor. (B) Selected region of interest labeled red bounding boxes after Photoshop processing. (C) The gray value of GIL. (D) EUS images of GIST, green arrow pointing to the tumor. (E) Selected region of interest labeled red bounding boxes after Photoshop processing. (F) The gray value of GIST.

Table 1. Baseline characteristics of the patients with histologically confirmed GISTs or GILs.

	GIL group	GIST group	p value
	n = 239	n = 233
Male (%)	65 (27.2)	80 (34.3)	.114
Age (year)	54.00 ± 10.72	60.24 ± 8.30	<.001
Diameter (cm)	1.01 ± 0.55	1.08 ± 0.64	.189

Table 2. Detailed of gray value and the mean ratio values of GISTs and GILs by Photoshop.

	GIL group n = 239	GIST group n = 233	p value
Tmean (mean ± SD)	57.70 ± 22.67	63.10 ± 23.29	.011
TSD (mean ± SD)	24.30 ± 8.26	26.24 ± 8.99	.015
Mmean (mean ± SD)	72.61 ± 21.04	68.82 ± 22.31	.059
MSD (mean ± SD)	9.24 ± 4.28	9.84 ± 3.49	.497
Smean (mean ± SD)	151.84 ± 33.99	151.54 ± 33.96	.925
SSD (mean ± SD)	20.38 ± 8.09	33.69 ± 7.59	.367
Wmean (mean ± SD)	29.21 ± 12.97	27.08 ± 11.84	.063
WSD (mean ± SD)	3.60 ± 2.00	3.28 ± 1.82	.070
TMratio (mean ± SD)	0.81 ± 0.28	0.97 ± 0.37	<.001
TSratio (mean ± SD)	0.38 ± 0.12	0.42 ± 0.14	<.001
TWratio (mean ± SD)	2.16 ± 1.02	2.65 ± 1.36	<.001

GIL: leiomyoma; GIST: gastrointestinal stromal tumor; Tmean: the gray value of tumor; Mmean: the gray value of muscularis propria; Smean: the gray value of submucosa; Wmean: the gray value of water; T_SD: the gray standard deviation of tumor; M_SD: the gray standard deviation of muscularis propria; S_SD: the gray standard deviation of submucosa; W_SD: the gray standard deviation of water; TMratio: the ratio of the gray value of tumor to muscularis propria; TSratio: the ratio of the gray value of tumor to submucosa; TWratio: the ratio of the gray value of tumor to water.

Figure 3. The area under the ROC curve of GISTs and GILs. (A) Tmean and T_sd; (B) Mmean, Smean, and Wmean; (C) TMratio, TSratio, and TWratio.

Table 3. Area under the curve, 95% CI, sensitivity, specificity, Youden Index and Cutoff point of datas for GISTs and GILs.

	AUC	95% CI	Sensitivity (%)	Specificity (%)	Youden Index	Cutoff point
Tmean	0.952	0.897–1.000	90.00	97.50	0.875	79.640
TSD	0.792	0.695–0.890	57.50	90.00	0.475	14.910
Mmean	0.479	0.393–0.649	47.50	67.50	0.150	66.550
Smean	0.625	0.499–0.746	42.50	80.0	0.225	164.780
Wmean	0.538	0.334–0.589	32.5	72.5	0.050	25.335
TMratio	0.917	0.844–0.991	92.50	95.00	0.875	1.097
TSratio	0.897	0.812–0.981	90.00	92.50	0.825	0.825
TWratio	0.929	0.870–0.987	87.50	92.50	0.800	3.236

Tmean: gray value of tumor; Mmean: gray value of muscularis propria; Smean: gray value of submucosa; Wmean: gray value of water; TMratio: the ratio of the gray value of tumor to muscularis propria; TSratio: the ratio of the gray value of tumor to submucosa; TWratio: the ratio of the gray value of tumor to water.

Figure 4. The sensitivity of Tmean, TMratio, TSratio, and TWratio for the diagnosis of GIL and GIST.