Clinical Significance of Frozen Section Analysis During Resection of Intraductal Papillary Mucinous Neoplasm: Should a Positive Pancreatic Margin for Adenoma or Borderline Lesion Be Resected Additionally?

BackgroundThe clinical significance of a positive intraoperative frozen section analysis of the pancreatic margin, especially for adenoma or borderline lesion, is not well understood during operations for intraductal papillary mucinous neoplasm of the pancreas.Study DesignData from 130 consecutive patients who underwent intraductal papillary mucinous neoplasm resection in a single institution were retrospectively analyzed.ResultsIn the first intraoperative frozen section analysis, 26 patients were positive for adenoma or borderline lesion, 10 for carcinoma in situ, 2 for cancer cells floating in the duct, and 6 for invasive cancer. Twenty-nine patients underwent additional resection, and 105 patients finally achieved a negative pancreatic margin. Among 18 patients with a positive pancreatic margin for adenoma or borderline lesion, only 1 had a recurrence. All 20 patients who suffered a recurrence harbored invasive intraductal papillary mucinous carcinoma in resected specimens. In multivariate analysis, predictive factors of recurrence after intraductal papillary mucinous carcinoma resection were the presence of lymph node metastasis, serosal invasion, and a high level of serum carbohydrate antigen 19-9.ConclusionsThe presence of adenoma or borderline lesion at the pancreatic margin does not always warrant further resection because of the low recurrence rate in the remnant pancreas. Recurrence after intraductal papillary mucinous neoplasm resection is influenced primarily by the presence and extent of invasive cancer rather than the status of the pancreatic margin.