Ha J, Choi SH, Kim KW, et al. - In this study, four significant MRI features were unveiled that can be useful to distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC), but diffusion-weighted imaging (DWI) assessment might be limited.

• A systematic search using three databases was conducted to determine significant MRI features for distinguishing AIP from PDAC.

• Total nine studies (775 patients) revealed the following significant MRI features for differentiating AIP from PDAC: multiple main pancreatic duct (MPD) strictures, absence of upstream marked MPD dilatation, peripancreatic rim, and duct penetration sign.

• The highest pooled sensitivity (87%) of absence of MPD dilatation was evident, whereas peripancreatic rim was shown to have the highest pooled specificity (100%).

• Of 12 studies assessing DWI, seven showed that apparent diffusion coefficient (ADC) values differed statistically significantly between AIP and PDAC; however, four documented lower ADC values in AIP vs in PDAC, but three demonstrated the opposite result.