Validation of the eighth edition of the American Joint Committee on Cancer staging system and proposal of an improved staging system for pancreatic ductal adenocarcinoma.

Compared with the seventh edition, the eighth edition of the AJCC staging system for pancreatic adenocarcinoma showed a more even distribution in T stage but marginal differences in other stages. The proposed system, using tumor size and number of metastatic lymph nodes, was better at predicting survival.