PMC

Kaplan-Meier curves for disease-free survival (A) and overall survival (B) in patients with pancreatic ductal adenocarcinoma who underwent PD after neoadjuvant therapy, stratified by ypT stage using the new AJCC Staging Manual (8^th edition).

Kaplan-Meier curves for disease-free survival (A) and overall survival (B) in patients with ypT1a or ypT1b, ypT1c and ypT2 pancreatic ductal adenocarcinoma who underwent PD after neoadjuvant therapy using the new AJCC Staging Manual (8^th edition). Patients with ypT1a or ypT1b disease have significantly longer disease-free survival and overall survival than those with ypT1c and those with ypT2 disease (p<0.05). However there is no significant difference in either disease-free survival or overall survival between the patients with ypT1c disease and those with ypT2 disease (p>0.05).

Prognostic significance of new ypT stage grouping in patients whose tumors were classified as ypT3 using the 7^th edition AJCC Staging Manual. Kaplan-Meier curves for disease-free survival (A) and overall survival (B) using the new AJCC Staging Manual (8^th edition) are shown. Patients with ypT1a or ypT1b disease have significantly longer disease-free survival and overall survival than those with ypT1c, ypT2 or ypT3 disease (p<0.05). However there is no significant difference in either disease-free survival or overall survival between the patients with ypT1c disease and those with ypT2 or ypT3 disease (p>0.05).

Schematic drawing to illustrate the method for tumor size measurement. For cases which had only single microscopic focus of viable residual tumor, the largest linear dimension of the viable tumor focus on H & E slide was used as the final tumor size (A). For cases which had more than one microscopic foci (multifocal) of viable residual tumor, the largest linear dimension of the area involved by all islands of viable residual tumor and the intervening fibrotic stroma was used as the residual tumor size (B). For cases which had microscopic viable residual tumor invading the pancreas and/or soft tissue beyond the tumor bed area, the largest dimension of the entire area involved by all islands of viable residual tumor with the intervening stroma, pancreas and/or soft tissue was used as the final tumor size (C).