Objective To improve the differential diagnosis between autoimmune pancreatitis (AIP) and pancreatic cancer (PC) by a contrast analysis of imageological features.Methods Thirty-six patients who had postoperative pathological with Asian AIP standards and 95 patients who had postoperative pathological consistent with PC.The imageological results of these AIP and PC patients were analyzed.Results AIP was significantly less than PC in the enhanced CT of a mass or enlargement of the pancreatic head,enlargement of the lymph nodes around the pancreas,dilation and interrupt in pancreatic and bile duct,peripheral vascular and organ involvement (11/27 vs.28/40,2/27 vs.17/40,13/27 vs.32/40,1/27 vs.10/40,8/27 vs.26/40,2/27 vs.15/40,0/27 vs.15/40,0/27 vs.10/40,P ＜ 0.05).AIP was significantly more than PC in the enhanced CT of a diffusely enlarged pancreas,calcification or pancreatic calculus,capsule-like rim or the vague peripancreatic fat interval (4/27 vs.0/40,7/27 vs.0/40,10/27 vs.6/40,P ＜ 0.05).AIP was significantly less than PC in the three-dimensional ultrasonography of dilation diameter of pancreatic duct and dilation of common bile duct [(0.421 ± 0.270) cm vs.(0.594 ± 0.270) cm,1/18 vs.16/26,P＜ 0.05].AIP was significantly less than PC in the magnetic resonance cholangiopancreatography of dilation of common bile duct and interrupt in pancreatic duct (7/13 vs.16/18,1/13 vs.10/18,P ＜ 0.05).Conclusion AIP as a unique type of chronic pancreatitis can be distinguished from PC on distinctive imageological features

Objective To improve the different diagnosis between autoimmune pancreatitis(AIP) and pancreatic cancer(PC) by a retrospective analysis of clinical symptoms and serological features.Methods The analysis included 36 patients who had postoperative pathological,serological findings consistent with Asian AIP standards and 95 patients who had postoperative pathological consistent with PC pathological standards.All patients were admitted by the surgery department of our hospital from January,2003 to October,2011.A retrospective comparative analysis of the clinical manifestations,serology data of these AIP and PC patients was conducted.And summary the differential diagnosis characteristics of AIP and pancreatic cancer in the clinical symptoms,the serology.Results The features of different diagnosis:(1) The age of patients with PC was higher than AIP((60.9 ±9.0) years vs.(53.56 ± 14.6) years,t =3.48,P ＜0.05),and AIP preferred to male groups (x2 =2.88,P =0.09).(2) The clinical features of AlP and PC with the age characteristics were easily confused.Both clinical features were relatively typical in younger age which could be found earlier and relatively insidious in the older age which might be found with delay.(3) AIP were often complicated by biliary system inflammations(AIP =47.2％,PC =12.6％,x2 =18.12,P ＜ 0.05),while PC were usually complicated by the cysts in liver and kidney (PC =29.5％,AIP =0,x2 =13.50,P ＜ 0.05).(4) The high titer in CA199 had a higher value in the diagnosis of PC (concentration:group AIP =20.51 (9.55,86.5) kU/L,group PC =326.50 (94.38,10393.00) kU/L; positive rate:group AIP =35.70％ (10/28),group PC =86.70％ (65/75),P =0.000).The high titers in amylase (concentration:group AIP =103.50 (72.00,252.00) U/L,group PC =46.50 (21.65,96.90) U/L; positive rate:group AIP =45.00％ (9/20),group PC =19.40％ (7/36),P =0.043),lipase(concentration:group AIP =340.50(152.05,495.80) U/L,group PC =107.40(23.40,177.26) U/L,P =0.005 ; aspartate aminotransferase (positive rate:group AIP =75.00％ (27/36),group,PC =55.90％ (52/93),P =0.046) andγ-glutamyltranspeptidase (positive rate:group AIP =79.40％ (27/34),group PC =57.10％ (52/91),P =0.022) had higher values in the diagnosis of AIP.The significant increases in CA199 were not the basis which excluding AIP.Conclusion AIP as a unique type of chronic pancreatitis can be distinguished from PC on distinctive clinical,serological characteristics.