Computed tomography radiogenomics: A potential tool for prediction of molecular subtypes in gastric stromal tumor

Table 1 Clinicopathological characteristics of gastrointestinal stromal tumor patients included in this study, n (%)

Characteristics	KIT exon 11 mutation (n = 192)	Without KIT exon 11 mutation (n = 39)	P value	KIT exon 11 mutation with deletions involving codons 557-558 (n = 56)	KIT exon 11 mutation without deletions involving codons 557-558 (n = 136)	P value
Gender (male)	97 (50.5)	24 (61.5)	0.223	32 (57.1)	65 (47.8)	0.268
Age	55.7 ± 11.5	53.8 ± 13.4	0.360	53.9 ± 13.5	56.4 ± 10.6	0.222
Mitosis
≤ 5/50 HPF	91 (47.4)	24 (61.5)	0.117	11 (19.6)	80 (58.8)	< 0.010
> 5/50 HPF	101 (52.6)	15 (38.5)		45 (80.4)	56 (41.2)
Risk classification
Very low	2 (1.0)	0 (0)	0.851	0 (0)	2 (1.5)	< 0.010
Low	43 (22.4)	10 (25.7)		4 (7.1)	39 (28.7)
Intermediate	59 (30.8)	13 (33.3)		7 (12.5)	52 (38.2)
High	88 (45.8)	16 (41.0)		45 (80.4)	43 (31.6)

Table 2 The computed tomography features of gastrointestinal stromal tumor patients included in this study, n (%)

Characteristics	KIT exon 11 mutation (n = 192)	Without KIT exon 11 mutation (n = 39)	P value	KIT exon 11 mutation with deletions involving codons 557-558 (n = 56)	KIT exon 11 mutation without deletions involving codons 557-558 (n = 136)	P value
Size (mm)	51 (11-224)	45 (10-201)	0.682	69 (31-224)	42.5 (11-188)	< 0.010
Shape
Regular	66 (34.4)	7 (17.9)	0.044	5 (8.9)	61 (44.9)	< 0.010
Irregular	126 (65.6)	32 (82.1)		51 (91.1)	75 (55.1)
Margin
Well-defined	168 (87.5)	23 (84.6)	0.625	44 (78.6)	124 (91.2)	0.016
Ill-defined	24 (12.5)	6 (15.4)		12 (21.4)	12 (8.8)
Growth pattern
Endophytic	64 (33.3)	6 (15.4)	0.083	12 (21.4)	52 (38.2)	0.010
Exophytic	87 (45.3)	22 (56.4)		25 (44.6)	62 (45.6)
Mixed	41 (21.4)	11 (28.2)		19 (33.9)	22 (16.2)
Density
Hypodensity	175 (91.1)	34 (87.2)	0.647	50 (89.3)	125 (91.9)	0.750
Isodensity	15 (7.8)	4 (10.3)		5 (8.9)	10 (7.4)
Hyperdensity	2 (1.0)	1 (2.6)		1 (1.8)	1 (0.7)
Pattern of enhancement
Homogeneous	48 (25.0)	5 (12.8)	0.099	5 (8.9)	43 (31.6)	0.001
Heterogeneous	144 (75.0)	34 (87.2)		51 (91.1)	93 (68.4)
Degree of enhancement
Mild	71 (37.0)	11 (28.2)	0.018	20 (35.7)	51 (37.5)	0.063
Moderate	75 (39.1)	10 (25.6)		28 (50.0)	47 (34.6)
Marked	46 (24.0)	18 (46.2)		8 (14.3)	38 (27.9)
Necrosis	121 (63.0)	28 (71.8)	0.296	43 (76.8)	78 (57.4)	0.011
Gas	33 (17.2)	4 (10.3)	0.282	14 (25.0)	19 (14.0)	0.066
Cystic change	6 (3.1)	4 (10.3)	0.046	0 (0)	6 (4.4)	0.110
Calcification	23 (12.0)	2 (5.1)	0.209	8 (14.3)	15 (11.0)	0.528
Superficial ulceration	55 (28.6)	10 (25.6)	0.704	19 (33.9)	36 (26.5)	0.299
Intra-tumoral vessel	86 (44.8)	14 (35.9)	0.307	34 (60.7)	52 (38.2)	0.004
Adjacent mesangial fat infiltration	40 (20.8)	9 (23.1)	0.755	20 (35.7)	20 (14.7)	0.001
Adjacent organ invasion	29 (15.1)	7 (17.9)	0.655	14 (25.0)	15 (11.0)	0.014
Lymphadenopathy	14 (7.3)	3 (7.7)	0.930	6 (10.7)	8 (5.9)	0.242
Distant metastasis	4 (2.1)	2 (5.1)	0.276	3 (5.4)	1 (0.7)	0.042

Table 3 Predictive performance of different model for KIT exon 11 mutation

Models	ModelCT sign		ModelCT sign + rad		ModelCT sign + rad + clinic
Cohort	Training	Validation	Training	Validation	Training	Validation
AUC	0.743	0.670	0.818	0.781	0.915	0.811
Accuracy	0.673	0.643	0.753	0.714	0.833	0.794
Sensitivity	0.815	0.672	0.667	0.690	0.938	0.830
Specificity	0.531	0.500	0.840	0.833	0.728	0.600
NPV	0.741	0.240	0.716	0.357	0.922	0.400
PPV	0.635	0.867	0.806	0.952	0.776	0.917

CT: Computed tomography; AUC: Area under the curve; NPV: Negative predictive value; PPV: Positive predictive value.

Table 4 Predictive performance of different model for KIT exon 11 codons 557-558 deletions

Models	ModelCT sign		ModelCT sign + rad		ModelCT sign + rad + clinic
Cohort	Training	Validation	Training	Validation	Training	Validation
AUC	0.667	0.610	0.842	0.782	0.872	0.795
Accuracy	0.522	0.500	0.689	0.700	0.720	0.766
Sensitivity	0.949	0.824	0.974	0.824	0.923	0.667
Specificity	0.385	0.396	0.598	0.660	0.656	0.796
NPV	0.959	0.875	0.986	0.927	0.964	0.886
PPV	0.330	0.304	0.437	0.438	0.462	0.500

CT: Computed tomography; AUC: Area under the curve; NPV: Negative predictive value; PPV: Positive predictive value.