Analysis of thromboembolism and prognosis in metastatic pancreatic cancer from the Tokushukai REAl-world data project

Cancer-associated thromboembolism (CAT), including venous thromboembolism (VTE) and arterial thromboembolism (ATE), is a frequent complication of advanced pancreatic cancer. However, reports on its incidence and clinical outcomes, especially on ATE, are limited. The present study aimed to investigate the incidence of CAT and its effects on overall survival in patients with metastatic pancreatic cancer. As part of the Tokushukai REAl-world data project in Japan, 846 eligible patients with metastatic pancreatic cancer treated with first-line chemotherapy were identified between April 2010 and March 2020. Using diagnosis procedure combination data from these patients, the present study investigated the incidence of VTE, ATE and cerebral and gastrointestinal bleeding requiring hospitalization. Blood laboratory data were collected within 14 days of the start of first-line treatment, and Khorana scores were calculated. The associations between CAT complications and comorbidities, concomitant medications and prognosis were examined. Among the 846 patients, 21 (2.5) and 70 (8.3%) had VTE and ATE, respectively (including five with overlapping VTE and ATE). CAT-positive patients had a significantly higher rate of gastrointestinal bleeding events compared with CAT-negative patients [13 of 86 (15.2%) vs. 46 of 760 (6.1%); P=0.01]. CAT-positive patients had a poorer prognosis [hazard ratio (HR), 1.28; 95% confidence interval (CI), 1.01-1.62] compared with CAT-negative patients, even after adjusting for background factors (HR, 1.20; 95% CI, 0.95-1.52). Cox regression analyses showed that higher Khorana scores were associated with significantly worse prognosis. This real-world data demonstrated that the incidence rate of CAT in patients with metastatic pancreatic cancer was 10.2%, and no statistically significant differences were observed, although there was a trend toward an adverse prognosis. The Khorana score may also be useful for predicting prognosis, even in the absence of CAT. This study was registered in the UMIN Clinical Trial Registry (http://www.umin.ac.jp/ctr/index.htm; clinical trial no. UMIN000050590).