Prognostic Validity of the Eighth Edition of the U.S. Joint Committee on Cancer TNM Staging System for Pancreatic Adenocarcinomas: An Analysis of 214 Patients at a Spanish Center.

Introduction: Accurate staging is essential in pancreatic adenocarcinoma due to its aggressive nature and poor prognosis. The 8th edition of the AJCC TNM staging system introduced changes in tumor size criteria and nodal classification. This study compares the prognostic performance of the 7th and 8th editions in resected patients. Material and Methods: A retrospective analysis was conducted on 214 patients with pancreatic adenocarcinoma who underwent curative surgery. TNM staging was assigned according to both AJCC editions. Kaplan-Meier analysis and multivariate Cox regression, stratified by adjuvant therapy, were used to assess disease-free survival (DFS) and overall survival (OS). Results: The 8th edition TNM staging was significantly associated with lower risk of recurrence, with TNM stages I and II independently predicting better DFS (p < 0.05). In contrast, the 7th edition TNM stage I remained the only independent predictor of OS (HR = 0.376; p = 0.023). Reclassification between editions altered stage distribution, particularly within stage II. Conclusions: The 8th edition improves early recurrence stratification, while the 7th edition retains stronger prognostic value for overall survival. Both systems offer complementary insights, supporting outcome-specific staging use.