Endoscopic ultrasonography can diagnose distal biliary strictures without a mass on computed tomography

Table 6 Diagnosis of malignant vs benign causes (%)

	Sensitivity	Specificity	PPV	NPV	Accuracy
EUS (n = 34)	94.1	82.3	84.2	93.3	88.2
Brushing (n = 24)	62.5a	100	100	57.2c	75.0
Tumor marker (CA19-9 > 37 U/mL) (n = 34)	76.5	70.6	72.2	75.0	73.5
Tumor marker (CA19-9 > 100 U/mL) (n = 34)	53.0b	82.4	75.0	63.6	67.7

^aP = 0.039 vs EUS;

^bP = 0.017 vs EUS;

^cP = 0.035 vs EUS. CA19-9: Carbohydrate antigen 19-9.