Association of Pretreatment Absolute Neutrophil Count and Prognostic Nutritional Index With Completion of Neoadjuvant Gemcitabine Plus S-1 in Resectable Pancreatic Cancer

Abstract

Background/Aim: Neoadjuvant chemotherapy with gemcitabine plus S-1 (NAC–GS) is used for resectable pancreatic cancer, but adverse events prevent some patients from completing planned therapy. This study examined associations of pretreatment absolute neutrophil count (ANC) and prognostic nutritional index (PNI) with NAC–GS completion and the perioperative treatment course. Patients and Methods: This single-center retrospective observational study included 93 patients with resectable pancreatic cancer who received NAC–GS from November 2019 to February 2025. NAC completion was defined as completing the two planned NAC–GS cycles, with or without dose reduction. Baseline hematologic, inflammatory, and nutritional parameters were assessed at NAC initiation. Multivariable logistic regression was used to examine factors associated with NAC discontinuation; receiver operating characteristic curve analysis determined ANC and PNI cutoff values. Results: Of 93 patients, 39 completed NAC–GS and 54 discontinued before completion, with all discontinuations attributed to adverse events. ANC and PNI were independently associated with NAC discontinuation in multivariable analysis. Their cutoff values were 2.6×103/μl and 43, respectively. NAC completion rates were significantly higher with ANC ≥2.6×103/μl than with ANC <2.6×103/μl (52.0% vs. 30.2%, p=0.03) and with PNI ≥43 than with PNI <43 (52.6% vs. 25.0%, p<0.01). Combined ANC/PNI stratification showed stepwise decreases in NAC completion, overall R0 resection rate, and R0 resection rate among patients who underwent pancreatectomy. Conclusion: Pretreatment ANC and PNI were independently associated with NAC–GS completion. Combined ANC/PNI stratification may offer a simple pretreatment method for estimating NAC–GS completion and the perioperative treatment course.