To Evaluate Whether Pretreatment <scp>CA19</scp> ‐9 and <scp>DUPAN</scp> ‐2 Levels Can Serve as Predictive Markers to Guide the Choice Between <scp>NAT</scp> and Upfront Surgery in Pancreatic Cancer

ABSTRACT Aim Pancreatic cancer (PC) remains one of the most lethal malignancies, with early recurrence severely affecting prognosis even after curative resection. While neoadjuvant treatments (NAT), such as gemcitabine plus S‐1 (NAT‐GS), have improved outcomes, predicting their effectiveness and optimizing patient selection remain challenging. This study aimed to investigate whether pretreatment CA19‐9 and DUPAN‐2 levels can serve as predictive markers to guide the choice between NAT and upfront surgery in pancreatic cancer. Methods We retrospectively analyzed 190 patients with PC (67 with NAT‐GS and 123 with upfront surgery). Patients were stratified into three groups based on their pre‐NAT CA19‐9/DUPAN‐2 levels: both within the reference range, one exceeding, or both exceeding. The 12 month recurrence‐free survival (12MRFS) rates were assessed using the Kaplan–Meier method, with log‐rank and other appropriate statistical tests for comparison. Results NAT‐GS was significantly more effective only in patients with one tumor marker above the reference range, comparing those who achieved 12 month MRFS with those who did not. In the Kaplan–Meier curve, among patients with only one elevated tumor marker, the NAT‐GS group showed a significantly better 12MRFS ratio than the upfront surgery group (78.6% vs. 51.2%, p = 0.034). Conclusion The combination of pre‐NAT CA19‐9 and DUPAN‐2 levels may serve as a useful criterion for selecting between upfront surgery, NAT‐GS, or more intensive chemotherapy. This suggests the possibility of a tailored approach, in which a combination of tumor markers would determine whether to opt for upfront surgery, NAT‐GS, or more intensive chemotherapy.