Metro-Pancreas Stratifies Survival After Neoadjuvant Chemotherapy and Surgery for Resectable Pancreatic Cancer

OBJECTIVE: To assess the prognostic utility of the Metro-Pancreas framework in resectable pancreatic ductal adenocarcinoma (PDAC) treated with neoadjuvant chemotherapy (NAT) and resection. SUMMARY BACKGROUND DATA: Upfront surgery and NAT are options in anatomically resectable PDAC. Metro-Pancreas combines tumor size and CA 19-9 to stratify prognosis after upfront resection, but its applicability after NAT is unknown. METHODS: We analyzed 623 patients with nonmetastatic, anatomically resectable PDAC who underwent NAT followed by resection from 5 institutions (2016-2024). Metro-Pancreas classification (IN/OUT) was determined by tumor size and CA19-9 levels. Treatment response followed NCCN 2026 definition based on radiologic and biochemical changes. Postoperative disease-free survival (DFS) and overall survival (OS) were evaluated. RESULTS: At diagnosis, 263 patients (42.2%) were Metro-Pancreas OUT and had shorter postoperative DFS (13.3 vs. 16.7 mo; P=0.003) and OS (29.5 vs. 34.8 mo; P=0.006) than Metro-Pancreas IN patients. After NAT, 71.9% of OUT patients were reclassified as IN, while 5.0% of initially IN patients became OUT. Among baseline OUT patients, 35.7% had significant response, 46.0% had minimal response, and 18.3% had progression. Prognostic separation was greater at Metro-Pancreas restaging (DFS: 7.7 vs. 17.3 mo; OS: 15.8 vs. 36.7 mo; both P=0.001). Patients reclassified from OUT to IN had postoperative DFS and OS comparable to those initially IN (P=0.806 and P=0.631, respectively). CONCLUSIONS: Among patients undergoing resection after NAT, Metro-Pancreas stratified prognosis at diagnosis and more effectively at restaging. Reclassification from OUT to IN was associated with favorable postoperative survival, supporting dynamic prognostic reassessment in the neoadjuvant setting.