Utility of pancreatography for diagnosing autoimmune pancreatitis

Table 1 Pancreatographic differences between autoimmune pancreatitis and pancreatic cancer n (%)

	Autoimmune pancreatitis (n = 48)	Pancreatic cancer (n = 143)	P-value
Obstruction of the MPD +/-	2/46 (4)	98/45 (69)	< 0.001
Skipped lesions of the MPD +/-	13/35 (27)	0/143 (0)	< 0.001
Side branch derivation from the narrowed MPD +/-	39/9 (81)	10/35 (22)	< 0.001
Length of the narrowed MPD (cm)	7.6 ± 4.3	2.5 ± 0.9	< 0.001
Length of the narrowed MPD > 3 cm +/-	43/5 (90)	12/33 (27)	< 0.001
Diameter of upstream MPD (mm)	2.9 ± 0.8	6.8 ± 2.1	< 0.001
Diameter of upstream MPD < 5 mm +/-	19/1 (95)	12/33 (27)	< 0.001

MPD: Main pancreatic duct.

Table 2 Cholangiographic differences between autoimmune pancreatitis and pancreatic cancer n (%)

	Autoimmune pancreatitis	Pancreatic carcinoma	P-value
Stenosis of the lower bile duct	n = 38	n = 77
Smooth stenosis	33 (87)	27 (35)	< 0.001
Irregular stenosis	5 (13)	50 (65)
Left-side deviation of the lower bile duct +/-	20 (53)	49 (64)	NS
Stenosis of the intra/hilar bile duct	6 (16)	0 (0)	0.001

NS: Not significant.

Table 3 Diagnostic accuracy for diffuse-type autoimmune pancreatitis by endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography

ERCP before steroid	MRCP
	Before steroid	After steroid
MPD narrowing	Skipped non-visualization 8 (50%)	Visualization 16/16 (100%)
(n = 16)	Faint visualization 3 (19%)
	Non-visualization 5 (31%)
Branches from the narrowed MPD (n = 14)	Faint visualization 3 (21%)	Visualization 7/14 (50%)
	Non-visualization 11 (79%)
Bile duct stenosis (n = 15)	Stenosis 15 (100%)	Resolution
		Complete 8/15 (53%)
		Incomplete 7/15 (47%)

ERCP: Endoscopic retrograde cholangiopancreatography; MRCP: Magnetic resonance cholangiopancreatography; MPD: Main pancreatic duct.

Table 4 Diagnostic accuracy for segmental-type autoimmune pancreatitis by endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography

ERCP before steroid	MRCP
	Before steroid	After steroid
MPD narrowing (n = 14)	Faint visualization 2 (14%)	Visualization 10/10 (100%)
	Non-visualization 12 (86%)
Branches from the narrowed MPD (n = 11)	Faint visualization 2 (18%)	Visualization 6/10 (60%)
	Non-visualization 9 (82%)
Bile duct stenosis (n = 8)	Stenosis 8 (100%)	Resolution
		Complete 4/8 (50%)
		Incomplete 4/8 (50%)

ERCP: Endoscopic retrograde cholangiopancreatography; MRCP: Magnetic resonance cholangiopancreatography; MPD: Main pancreatic duct.