Elevated preoperative plasma D-dimer level was an independent prognostic factor for patients with PDAC after curative resection: a retrospective analysis

Abstract

Objective: In this study, the relationship between preoperative plasma D-dimer level and overall survival and recurrence free survival were evaluated in patients with curative resection of pancreatic ductal adenocarcinoma.

Methods: Preoperative plasma D-dimer level of 573 patients with pancreatic ductal adenocarcinoma were collected. The univariate and multivariate Cox hazard models were used to identify independent variables associated with overall survival and recurrence free survival in this study. The Kaplan-Meier method was used to evaluate overall survival and recurrence free survival, and the differences between survival curves were analyzed using the Log-rank test. Continuous variables were presented as $\overline{x}\pm s$, parametric analysis was performed using t-test. Categorical variables were analyzed by means of the chi-square or Fisher's exact test.

Results: Based on the analysis for the whole study, the results showed that patients in the elevated plasma D-dimer levels had a tendency to have an elder mean age (58.69 ± 8.32 years vs. 63.05 ± 8.44 years, P < 0.001), larger tumour size ≥4 cm (P = 0.006), advanced T stage (P = 0.024), N stage (P = 0.041), Tumor, Node and Metastasis (TNM) stage (P = 0.029) and postoperative complications (P = 0.042) was more likely occurred. Besides, according to the results of Cox multivariate analysis, elevated preoperative plasma D-dimer level was an independent prognostic factor not only for overall survival (Hazard Ratio (HR):1.430, 95% Confidence Interval (CI) (1.163-1.759), P = 0.001) but also for recurrence free survival (HR:1.236, 95% CI (1.018-1.500), P = 0.032).

Conclusion: In our study, the elevated preoperative plasma D-dimer level may act as an independent prognostic factor for overall survival and recurrence free survival in patients with pancreatic ductal adenocarcinoma after curative resection. Pancreatic ductal adenocarcinoma patients with elevated preoperative plasma D-dimer level had a worse prognosis than those with normal plasma D-dimer level; and the elevated preoperative plasma D-dimer level may imply heavy tumour burden and provide supplementary information regarding disease status.

Keywords: D-dimer; pancreatic ductal adenocarcinoma; prognosis.