Diffusion MRI for Pancreatic Adenocarcinoma

Use of Diffusion-weighted MRI for the Detection of Liver Metastases in Potentially Resectable Pancreatic Adenocarcinomas: a Prospective Multicenter Study

The detection of small liver metastases represents a major challenge during the staging process of patients with pancreatic adenocarcinoma. Currently, thoraco-abdominopelvic CT represents the established imaging modality for selecting patients with pancreatic adenocarcinoma for curative surgery. However, despite its performance, 13% to 23% of patients undergoing a surgical procedure are finally found to have an unresectable disease because of arterial involvement, peritoneal carcinomatosis, or the existence liver metastasis that had not been detected by preoperative workup. Compared to CT, diffusion-weighted MRI provides a better contrast resolution for soft tissue and liver imaging, and thus leads to a better detection of focal liver lesions. Hence, it could be hypothesized that the use of DW-MRI in patients with potentially resectable PA may improve the selection process of candidates for curative pancreatic resection by increasing the detection of LM undiagnosed by traditional preoperative work-up

Inclusion Criteria:

• age > 18 year old,
• no general contraindication for pancreatic surgery,
• pancreatic mass suspected or demonstrated to be a pancreatic adenocarcinoma,
• CAP CT of excellent technical quality showing a pancreatic tumor deemed resectable or border line (portal and/or superior mesenteric venous circumferential involvement < 180°
• Resectability confirmed by a medical/surgical multidisciplinary review,
• if neoadjuvant therapy was applied, patients were included in the study: only the second evaluation will be considered.
• informed consent prepared and signed.

Exclusion Criteria:

• locally advanced pancreatic adenocarcinoma (involvement > 180°in circumference of superior mesenteric venous (SMV) or portal vein, superficial vein thrombosis, superior mesenteric artery (SMA) involvement < 180°)
• unresectable tumour (circumferential involvement > 180 ° of the SMA, involvement of the celiac artery, thrombosis of the portal vein or vena cava, or complete VMS thrombosis
• metastasis of any organ visible on thoraco-abdominopelvic CT scan
• time lag exceeding 21 days between diffusion-weighted MRI and surgery
• contraindication for an MRI