Abstract

Abstract
Aim
To evaluate the prognostic value of the CA 19-9 elimination rate on survival in patients with metastatic pancreatic cancer.
Materials and Methods
This single-center retrospective cohort study included 103 adult patients with metastatic pancreatic ductal adenocarcinoma who received systemic therapy. The CA 19-9 elimination rate was calculated using baseline and 3-month values. The optimal cut-off value was determined using maximally selected rank statistics. Overall survival was analyzed using the Kaplan–Meier method and Cox proportional hazards regression.
Results
The mean age of the patients was 64 ± 10.1 years, and the overall mortality rate during follow-up was 87.4%. No significant differences were observed between mortality groups with respect to demographic, clinical, or pathological characteristics (all p > 0.05). The optimal cut-off value for the elimination rate(ER) was 2.33 (ER ≥ 2.33: high elimination; < 2.33: low elimination). Median overall survival was 25 months (95% CI: 17–31) in the high-elimination group and 8 months (95% CI: 7–14) in the low-elimination group (p = 0.043). The 12-, 36-, and 60-month survival rates were 80.4%, 18.3%, and 11% in the high-elimination group, compared with 37.6%, 2.2%, and 0% in the low-elimination group.
Conclusion
The CA 19-9 elimination rate is a significant prognostic biomarker for survival in patients with metastatic pancreatic cancer. A higher elimination rate is associated with longer survival and improved short- and long-term survival outcomes, suggesting its potential utility for risk stratification and treatment response assessment in clinical practice.

Key words: Keywords: Pancreatic cancer; CA 19-9; elimination rate; metastatic disease; prognostic biomarker