Abstract

Introduction: Pancreatic ductal adenocarcinoma (PDAC) is associated with a very poor prognosis, early locoregional recurrence and rapid development of distant metastases. One of the reasons for this is a high rate of perineural invasion.

Aim: To demonstrate the role of extrapancreatic perineural invasion in development of locoregional recurrence of PDAC.

Results: In 14.5% of cases (22/152), the tumor was localized within the pancreas, which corresponded to pT1-2, pN0, extrapancreatic perineural invasion (EPn) 0, R0. R1 was identified in 32.1% of cases (49/152). Extrapancreatic perineural invasion was detected in 36.8% of cases (56/152). Metastases in the regional lymph nodes were revealed in 62.5% of cases (95/152) of patients. The analysis of the autopsy material demonstrated that the main morphological parameters of tumor development include locoregional progression and/or distant progression. Locoregional recurrence was identified in 85% of cases (29/34) and manifested as extrapancreatic perineural invasion in the bed of the removed tumor. The average length of time from surgery to locoregional recurrence without EPn was 14 ± 3 months, with EPn - 9 ± 2,5 months.

Conclusion: Locoregional recurrence in patients is directly related to the presence of extrapancreatic perineural invasion. The identified subpopulation of patients without distant progression but only with locoregional recurrence dictates the need for a combined treatment approach that leads to an increase of overall survival in patients with PDAC.

Keywords: Pancreatic Ductal Adenocarcinoma; Locoregional Recurrence; Perineural Invasion

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