Recurrence patterns of intraductal papillary mucinous neoplasms of the pancreas on enhanced computed tomography

To characterize imaging features and findings in recurrent intraductal papillary mucinous neoplasms (IPMN); thereby reconciling the "field defect" theory with the appearance of recurrences distant from the resection margin.

Computed tomography findings were reviewed in 89 patients who were resected with IPMN. At follow-up, the appearance of the pancreatic duct, features of recurrent masses, evidence of enhancement, calcifications, lymphadenopathy, and metastases were recorded.

Fourteen (16%) of the 89 patients had evidence of recurrence. Nine (64%) of the 14 patients demonstrated evidence for local recurrence. Ten recurrent lesions were noted in 9 patients. Patients with recurrence demonstrated an increase of pancreatic ductal dilatation of 3.3 mm, whereas patients without recurrence either had no dilatation or dilatation which then decreased over time.

Computed tomography findings suspicious for tumor recurrence include enlarging mass (either solid, cystic or both), progressive ductal dilatation, or extrapancreatic disease. There was a lack of correlation between margin status and location of recurrence within the pancreas consistent with the global field defect theory of IPMN.