Background Previous studies regarding survival in patients with splanchnic vein thrombosis (SVT) are limited. This study measured overall survival in a large cohort of SVTs through linkage to population-based data. Methods and Results Using a previously derived text-search algorithm, we screened the reports of all abdominal ultrasound and contrast-enhanced computed tomography studies at The Ottawa Hospital over 14 years. Screen-positive reports were manually reviewed by at least 2 authors to identify definite SVT cases by consensus. Images of uncertain studies were independently reviewed by 2 radiologists. One thousand five hundred sixty-one adults with SVT (annual incidence ranging from 2.8 to 5.9 cases/10 000 patients) were linked with population-based data sets to measure the presence of concomitant cancer and survival status. Thrombosis involved multiple veins in 314 patients (20.1%), most commonly the portal vein (n=1410, 90.3%). Compared with an age-sex-year matched population, patients with SVT had significantly reduced survival in particular with local cancer (adjusted relative excess risk for recent cases 12.0 [95% CI, 9.8-14.6] and for remote cases 9.7 [7.7-12.2]), distant cancer (relative excess risk for recent cases 5.7 [4.5-7.3] and for remote cases 5.4 [4.4-6.6]), cirrhosis (relative excess risk 8.2 [5.3-12.7]), and previous venous thromboembolism (relative excess risk 3.8 [2.4-6.0]). One hundred fifty (23.9%) of patients >65 years of age were anticoagulated within 1 month of diagnosis. Conclusions SVT is more common than expected. Most patients have cancer and the portal vein is by far the most common vein involved. Compared with the general population, patients with SVT had significantly reduced survival, particularly in patients with concomitant cancer, cirrhosis, and previous venous thromboembolic disease. Most elderly patients did not receive anticoagulant therapy.
Keywords: cancer; cirrhosis; computerized tomography; relative survival; splanchnic vein thrombosis.