The aim of the study is to evaluate the utility of secretin-enhanced MRI (S-MRI) in detecting and measuring pancreatic lesions in patients with known adenocarcinoma or Intraductal papillary mucinous neoplasm (IPMN) lesions. The hypothesis is that S-MRI is superior to MRI without secretin enhancement (N-MRI) in increasing tumor conspicuity, allowing for improved identification and more accurate measurement of lesions or precursor lesions in the pancreas.