Correlation of dynamic contrast-enhanced ultrasonography and the Ki-67 labelling index in pancreatic ductal adenocarcinoma

Table 3 Comparison of quantitative parameters between the pancreatic ductal adenocarcinoma lesions and pancreatic parenchyma

Parameters	Tumor	Parenchyma	P value
The high Ki-67 expression group
CAT	4.66 (3.12, 11.33)	5.10 (4.28, 11.19)	0.457
FT	36.46 (25.29, 49.72)	28.24 (21.38, 38.44)	0.209
HDT	51.56 (44.12, 59.09)	47.76 (41.11, 61.04)	0.739
PE	5.31 × 107 (3.31 × 107, 7.54 × 107)	1.09 × 108 (6.43 × 107, 1.77 × 108)	0.006a
RT	12.31 (10.33, 18.11)	12.44 (8.21, 14.34)	0.293
TTP	20.92 (16.24, 25.17)	18.42 (13.15, 26.74)	0.369
WiAUC	3.98 × 108 (2.46 × 108, 8.48 × 108)	7.51 × 108 (5.02 × 108, 1.11 × 109)	0.038a
WiPI	3.32 × 107 (2.15 × 107, 4.80 × 107)	6.86 × 107 (3.97 × 107, 1.08 × 108)	0.006a
WiR	6.40 × 106 (3.94 × 106, 9.05 × 106)	1.72 × 107 (8.70 × 106, 2.68 × 107)	0.004a
WiWoAUC	1.70 × 109 (9.58 × 108, 2.16 × 109)	3.51 × 109 (1.68 × 109, 3.61 × 109)	0.026a
WoAUC	1.03 × 109 (6.94 × 108, 1.52 × 109)	2.55 × 109 (1.20 × 109, 2.80 × 109)	0.015a
WoR	-2.05 × 106 (-3.75 × 106, -8.11 × 105)	-3.46 × 106 (-7.13 × 106, -2.86 × 106)	0.033a
mTT	18.25 (14.61, 27.72)	18.33 (11.83, 22.52)	0.555
The low Ki-67 expression group
CAT	6.99 (4.76, 12.63)	7.52 (5.03, 12.42)	0.986
FT	37.95 (25.28, 43.16)	35.55 (22.82, 54.05)	0.877
HDT	47.68 (40.47, 56.70)	62.98 (45.22, 81.97)	0.117
PE	8.05 × 107 (5.06 × 107, 1.22 × 108)	1.17 × 108 (9.61 × 107, 1.63 × 108)	0.065
RT	13.47 (11.56, 16.13)	12.28 (11.69, 21.52)	0.850
TTP	21.28 (18.02, 24.76)	22.43 (18.36, 26.92)	0.524
WiAUC	6.77 × 108 (4.34 × 108, 1.02 × 109)	1.02 × 109 (6.58 × 108, 1.68 × 109)	0.060
WiPI	5.07 × 107 (3.15 × 107, 7.38 × 107)	7.52 × 107 (5.92 × 107, 1.01 × 108)	0.060
WiR	9.63 × 106 (4.33 × 106, 1.33 × 107)	1.27 × 107 (7.60 × 106, 1.89 × 107)	0.185
WiWoAUC	2.19 × 109 (1.46 × 109, 3.46 × 109)	3.18 × 109 (2.12 × 109, 7.45 × 109)	0.048a
WoAUC	1.63 × 109 (1.05 × 109, 2.46 × 109)	2.35 × 109 (1.55 × 109, 5.39 × 109)	0.071
WoR	-2.63 × 106 (-3.73 × 106, -1.47 × 106)	-3.10 × 106 (-7.64 × 106, -2.08 × 106)	0.249
mTT	22.12 (16.89, 24.99)	18.09 (17.14, 31.93)	0.918

^aP < 0.05.

CAT: Contrast agent arrival time; FT: Fall time; HDT: Half-decrease time; PE: Peak enhancement; RT: Rise time; TTP: Time to peak; WiAUC: Wash-in area under the curve; WiPI: Wash-in perfusion index; WiR: Wash-in rate; WiWoAUC: Wash-in and wash-out area under the curve; WoAUC: Wash-out area under the curve; WoR: Wash-out rate; mTT: Mean transit time.