Slow-pull and different conventional suction techniques in endoscopic ultrasound-guided fine-needle aspiration of pancreatic solid lesions using 22-gauge needles

Table 1 Patient characteristics and final diagnosis of endoscopic ultrasound-guided fine-needle aspiration (n = 102)

Characteristic	Value
Median age (range), yr	53 (19-82)
Sex, male:female, n	67:35
Median tumor size (range), mm	34 (8-89)
Endoscopist, endoscopist 1:endoscopist 2, n	45:57
Location, uncinate or head:body or tail, n	59:43
Median number of passes, n	3 (1-5)
Final diagnosis, n
Malignant	58
Pancreatic cancer	53
Neuroendocrine tumor, malignant	2
Solid-pseudopapillary neoplasm, malignant	3
Benign	44
Chronic pancreatitis	23
Autoimmune pancreatitis	7
Nonspecific inflammation	10
Cystadenoma, benign	2
Neuroendocrine tumor, benign	1
Benign lymphangioma	1

Table 2 Baseline characteristics of the different suction techniques

	Slow-pull	5-mL	10-mL	20-mL	P value1
	(n = 31)	(n = 19)	(n = 34)	(n = 18)
Median age (range), yr	56 (20-82)	54 (38-71)	51 (19-77)	49 (26-73)	0.949
Sex, male:female, n	17:14	11:8	25:9	14:4	0.238
Median lesion size (range), mm	25 (8-72)	38 (10-65)	36 (17-89)	35 (16-62)	0.0312
Endoscopist, endoscopist 1:endoscopist 2, n	13:18	11:8	11:23	10:8	0.223
Location, uncinate or head:body or tail, n	19:12	11:8	16:18	13:5	0.348
Median number of passes, n	3 (1-4)	3 (2-5)	3 (1-5)	3 (2-5)	0.280

¹χ² test for categorical variables and Kruskal-Wallis H test for continuous variables;

²Statistically significant.

Table 3 Cytological diagnostic capacity and specimen quality of the different suction techniques

	Slow-pull (n = 31)	5-mL (n = 19)	10-mL (n = 34)	20-mL (n = 18)	P value1
Cytological diagnostic capacity
Accuracy	28/31 (90.3%)	12/19 (63.2%)	20/34 (58.8%)	10/18 (55.6%)	0.0192
Sensitivity	15/17 (88.2%)	5/12 (41.7%)	8/20 (40.0%)	4/11 (36.4%)	0.0092
Specificity	13/14 (92.9%)	7/7 (100%)	12/14 (85.7%)	6/7 (85.7%)	0.914
PPV	15/16 (93.8%)	5/5 (100%)	8/10 (80.0%)	4/5 (80.0%)	0.542
NPV	13/15 (86.7%)	7/14 (50.0%)	12/24 (50.0%)	6/13 (46.2%)	0.079
Cytological specimen quality
Cellularity score ≥ 2	22/31 (71.0%)	11/19 (57.9%)	20/34 (58.8%)	13/18 (72.2%)	0.598
Blood contamination score ≥ 2	9/31 (29.0%)	10/19 (52.6%)	24/34 (70.6%)	13/18 (72.2%)	0.0032

¹Fisher’s exact test for “specificity” and “PPV”; χ² test for the rest;

²Statistically significant. PPV: Positive predictive value; NPV: Negative predictive value.

Table 4 Comparisons between the slow-pull technique and conventional suction techniques in terms of cytological diagnostic accuracy, sensitivity and blood contamination

	5-mL	10-mL	20-mL
	vs slow-pull, P value1
Accuracy	0.032	0.0052	0.0102
Sensitivity	0.0142	0.0062	0.0102
Blood contamination score ≥ 2	0.135	0.0012	0.0072

¹Fisher’s exact test;

²Statistically significant.

Table 5 Univariate and multivariate analyses of factors affecting cytological diagnostic accuracy

Variable		Accuracy	Univariate	Multivariate
			P value1	P value2	OR (95%CI)
Lesion size	≤ 30 mm	74.4% (32/43)	0.282	0.603	1.29 (0.50-3.36)
	> 30 mm	64.4% (38/59)
Endoscopist	Endoscopist 2	71.9% (41/57)	0.419	0.367	1.52 (0.61-3.74)
	Endoscopist 1	64.4% (29/45)
Location	Body or tail	69.8% (30/43)	0.832	0.687	1.21 (0.48-3.04)
	Uncinate or head	67.8% (40/59)
Needle passes	≤ 3	69.7% (46/66)	0.753	0.233	1.81 (0.68-4.79)
	> 3	66.7% (24/36)
Suction techniques	Slow-pull	90.3% (28/31)	0.0193	0.0053	1.91 (1.21-3.00)
	5-mL	63.2% (12/19)
	10-mL	58.8% (20/34)
	20-mL	55.6% (10/18)

¹χ² test;

²Logistic regression analysis;

³Statistically significant.