Abstract
Objective: Systemic inflammation, nutritional status, and metabolic reserve are recognized determinants of survival in metastatic gastric cancer patients. The serum albumin-to-creatinine ratio (ACR) combines nutritional and renal/metabolic information, but its prognostic value in gastric cancer remains unclear. We aimed to investigate the association between baseline ACR and survival outcomes in patients with de novo metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric cancer.
Material and Method: This retrospective, single-center study included 112 adults with histologically confirmed de novo metastatic HER2-negative gastric cancer diagnosed between April 2011 and January 2024. Baseline serum albumin and creatinine levels obtained within 15 days prior to treatment initiation were used to calculate the ACR. Patients were categorized into low and high ACR groups according to the cohort median. Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and Cox proportional hazards models.
Results: The median follow-up duration was 40.6 months. The median PFS for the entire cohort was 6.8 months, and the median OS was 13.7 months. Patients with high ACR had significantly longer PFS (7.2 vs. 6.0 months; p=0.005) and OS (16.9 vs. 10.2 months; p<0.001) than those with low ACR. In multivariable analysis, high ACR remained independently associated with improved PFS [hazard ratio (HR): 0.65; 95% confidence interval (CI): 0.44-0.97; p=0.034) and OS (HR: 0.38; 95% CI: 0.21-0.67; p<0.001)]. Eastern Cooperative Oncology Group performance status ≥1 was also independently associated with worse survival outcomes.
Conclusion: Baseline serum ACR is an independent prognostic marker for both PFS and OS in patients with de novo metastatic HER2-negative gastric cancer. As a simple and routinely available laboratory parameter, ACR may contribute to risk stratification in advanced disease.