Venous thromboembolic complications in patients newly diagnosed with cholangiocarcinoma.

Cholangiocarcinoma (CCA) is an uncommon cancer, with limited data available on the incidence of cancer-associated thrombosis in CCA patients. This was a single-center, retrospective study conducted in a university-based hospital in Thailand. We included consecutive patients newly diagnosed with CCA between January 2019 and December 2022. The study outcomes focused on the incidence of venous thromboembolism (VTE) and all-cause mortality within 12 months of diagnosis. A total of 450 patients were included in the study, with a median follow-up time of 212 days, and 61.8% of participants were male. The one-year incidence of VTE was 15.3%, with a median time to VTE occurrence of 6 days (Q1-Q3: 1-86 days). Multivariable analysis indicated that age ≤ 55 years (hazard ratio 2.34, 95% confidence interval [CI] 1.40-3.88, p = 0.001), ECOG performance status ≥ 2 (HR 2.53, 95% CI 1.41-4.53, p = 0.002), stage IV cancer (HR 1.84, 95% CI 1.14-3.00, p = 0.013), and total bilirubin ≤ 13 mg/dL (HR 4.11, 95% CI 1.67-10.15, p = 0.002) were associated with VTE occurrence. During follow-up, all-cause mortality was 57.3%, and VTE presence increased the risk of all-cause mortality, with an HR of 1.41 (95% CI 1.02-1.94, p = 0.035). The incidence of VTE following a diagnosis of CCA was notably high. CCA patients who developed VTE were observed to be at a heightened risk of all-cause mortality. Therefore, VTE should be recognized as one of the significant complications among CCA patients.