Prognostic and Clinicopathological Significance of C-Reactive Protein to Albumin Ratio in Patients with Bile Duct Cancer: A Meta-Analysis.

Recent studies have explored the prognostic role of the C-reactive protein to albumin ratio (CAR) in patients with bile duct cancer (BTC), but the results have been inconsistent. This study aimed to provide insight into the prognostic significance of the CAR in BTC prior to treatment using a meta-analysis. Summarized hazard ratios (HRs) or odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for prognosis and clinicopathological features using fixed or random effects models. Fourteen studies with a total of 1,543 subjects were included in this meta-analysis. Elevated CAR was significantly associated with poor overall survival (HR = 2.17, 95% CI = 1.81-2.60,  < 0.001) and decreased disease-free survival or recurrence-free survival (HR = 2.53, 95% CI = 1.98-3.25,  < 0.001) in BTC. In addition, high CAR was significantly associated with the presence of lymph node metastasis (OR = 1.54, 95% CI = 1.12- 2.13,  = 0.008), bile duct invasion (OR = 2.64, 95% CI = 1.54-4.54,  < 0.001), and tumor stages III-IV (OR = 3.11, 95% CI = 1.05-9.20,  = 0.040). However, there was no significant association between CAR and sex, microvascular invasion, or resection. An elevated CAR was significantly related to worse long-term and short-term survival and advanced clinicopathological features of BTC. CAR could serve as a valuable, noninvasive prognostic marker in patients with BTC.