Absence of pancreatic intraepithelial neoplasia predicts poor survival after resection of pancreatic cancer.

OBJECTIVES: Pancreatic intraepithelial neoplasia (PanIN), thought to represent the dominant precursor of pancreatic adenocarcinoma (PDAC), is often found synchronously adjacent to resected PDAC tumors. However, its prognostic significance on outcome after PDAC resection is unknown.

METHODS: A total of 342 patients who underwent resection for PDAC between 2005 and 2010 at a single institution were identified and stratified according to highest grade of PanIN demonstrated surrounding the tumor. Clinical and pathologic characteristics of each patient and tissue were recorded and analyzed. The primary outcome was length of survival after resection.

RESULTS: An absence of PanIN lesions was identified in 32 patients (9%), low grade PanIN without synchronous high grade lesions was identified in 52 patients (15%), and high grade PanIN was found in 258 patients (75%). Median survival were 12.8 months for the non-PanIN group, 26.3 months for the low-grade PanIN group, and 23.8 months for the high-grade PanIN groups (P = 0.043). In multivariable analysis, absence of PanIN was independently associated with poor survival (P = 0.002).

CONCLUSIONS: The patients who demonstrate an absence of PanIN in the pancreatic tissue adjacent to the resected PDAC tumor have shorter postresection survival compared with those who demonstrate a PanIN lesion.