Dilatation of the main pancreatic duct as first manifestation of small pancreatic ductal adenocarcinomas detected in a hereditary pancreatic cancer surveillance program.

Background: MRI surveillance in a cohort of CDKN2A-p16-Leiden mutation carriers with a 20% lifetime risk of PDAC led to increased resection rates and improved survival. Patients with screen-detected PDAC were evaluated for main pancreatic duct (MPD) abnormalities in this retrospective review.

Methods: Since 2000 annual MRI and optional EUS was performed in mutation carriers. Data of patients with screen-detected PDAC was collected on gender, age at diagnosis, site of tumor, size, outcome of surgery, pathology findings and survival. All MRIs were re-evaluated for MPD abnormalities.

Results: 23 PDAC were detected in 22 (10%) of 217 mutation carriers, 10 (45%) males and 12 (55%) females. The mean age at diagnosis was 59.8 years (range 39.2-74.3 years). Revision of the MRI/MRCP revealed a lesion and dilatation of the MPD in 8 of the 22 patients. In 5 of 7 patients with PDAC detected during follow-up, the previous MRI showed MPD dilatation without evidence of tumor. The mean size of PDAC was 12.3 mm (range 5-19 mm). All tumors were resectable.

Conclusion: MPD dilation is common in patients with screen-detected PDAC. Abnormalities on MRI during surveillance of high-risk individuals requires intense follow-up or prompt treatment, as early treatment results in a better prognosis.