Acute pancreatitis in intraductal papillary mucinous neoplasm: Associations with epithelial subtype, degree of dysplasia, and risk of recurrence.

BACKGROUND

Acute pancreatitis is an uncommon presentation of intraductal papillary mucinous neoplasm; however, it is considered a worrisome feature in current guidelines and can be an indication for surgery. There is controversy regarding its association with malignancy, and there is little information regarding the recurrence of pancreatitis after surgical resection.

METHODS

We retrospectively reviewed patients who underwent resection for intraductal papillary mucinous neoplasm at a single institution between January 1990 and December 2023. Patients with and without acute pancreatitis as part of the clinical presentation were compared.

RESULTS

A total of 812 patients were reviewed. Of these, 156 patients (19.2%) had intraductal papillary mucinous neoplasms associated with acute pancreatitis, and in 92% of them pancreatitis was the symptom leading to the diagnosis. Half of the patients had a single episode of pancreatitis (n = 77, 49.4%), and 42 (26.9%) had had 3 or more episodes before diagnosis. Acute pancreatitis was significantly associated with high-grade dysplasia (odds ratio 2.07) but had a lower likelihood of invasive cancer (odds ratio 0.62). It was also significantly associated with main duct and mixed duct-type intraductal papillary mucinous neoplasm (odds ratio 1.97) and intestinal epithelial subtype (odds ratio 2.28). Median follow-up for all patients was 61 months, and the likelihood of recurrent pancreatitis after surgical resection was 9% (14 patients), whereas pancreatitis after resection in patients without prior history occurred in only 0.9% (6 patients, P < .001).

CONCLUSIONS

Almost 1 in 5 patients undergoing resection for intraductal papillary mucinous neoplasm have a history of acute pancreatitis and are twice as likely to have high-grade dysplasia, supporting its categorization as a worrisome feature. Recurrence of pancreatitis after resection was 9%.