The prognostic value of combined preoperative PLR and CA19-9 in patients with resectable gallbladder cancer

The platelet to lymphocyte ratio (PLR) is the marker of host inflammation and it is a potential significant prognostic indicator in various different tumors. The serum carbohydrate antigen 19–9 (CA19-9) is a tumor-associated antigen and it is associated with poor prognosis of gallbladder cancer (GBC). We aimed to analyze the prognostic value of the combination of preoperative PLR and CA19-9 in patients with GBC. A total of 287 GBC patients who underwent curative surgery in our institution was included. To analyze the relationship between PLR and CA19-9 and clinicopathological features. A receiver operating characteristic (ROC) curve was used to identify the optimal cutoff value for PLR and CA19-9. The Kaplan–Meier method was used to estimate the overall survival (OS). Meanwhile, the univariate and multivariate Cox regression models were used to assess the risk factors for OS. The cutoff values of 146.82 and 36.32U/ml defined as high PLR and high CA19-9, respectively. Furthermore, survival analysis showed that patients with PLR > 146.82 and CA19-9 > 36.32 U/ml had a worse prognosis than patients with PLR ≤ 146.82 and CA19-9 ≤ 36.32 U/ml, respectively. The multivariate analysis demonstrated that PLR (hazard ratio (HR) = 1.863, 95% CI: 1.366–2.542, P < 0.001) and CA19-9 (HR = 1.412, 95% CI: 1.021–1.952, P = 0.037) were independent prognostic factors in the GBC patients. When we combined these two parameters, the area under the ROC curve increased from 0.624 (PLR) and 0.661 (CA19-9) to 0.711. In addition, the 1-, 3-, and 5-year OS of group A (patients with PLR ≤ 146.82 and CA19-9 ≤ 36.32 U/ml), group B (patients with either of PLR > 146.82 or CA19-9 > 36.32 U/ml) and group C (patients with PLR > 146.82 and CA19-9 > 36.32 U/ml) were 83.6%, 58.6%, 22.5%, 52.4%, 19.5%, 11.5%, and 42.3%, 11.9%, 0%, respectively. The preoperative PLR and serum CA19-9 are associated with prognosis of patients with GBC. The combination of PLR and CA19-9 may serve as a significant prognostic biomarker for GBC patients superior to either PLR or CA19-9 alone.