Splanchnic Venous Thrombosis is a Marker of Cancer and a Prognostic Factor for Cancer Survival

SUMMARY: The Center for Disease Control and Prevention (CDC) estimates that approximately 1-2 per 1000 individuals develop Deep Vein Thrombosis/Pulmonary Embolism (PE) each year in the United States, resulting in 60,000 – 100,000 deaths. VTE is the third leading cause of cardiovascular mortality. Patients with unprovoked DVT and PE are two to four times more likely to be diagnosed with cancer within the following 12 months compared to the general population. It is however unknown if Splanchnic Venous Thrombosis (splanchnic veins carry blood through the liver and other abdominal organs) is a marker of occult cancer and a prognostic factor for cancer survival.

To address this question the authors from Denmark conducted a nationwide cohort study using Danish medical registries and included 1,191 patients with first time Splanchnic Venous Thrombosis (SVT) between 1994 and 2011, and followed them for subsequent cancer diagnosis, for a median of 1.6 years. They compared these results with the expected cancer risk in the general population. Additionally, to evaluate the impact of SVT on survival in those patients with cancer, the researchers compared survival in these cancer patients with a matched cohort of cancer patients without SVT. In the cohort of 1,191 patients with first time Splanchnic Venous Thrombosis (SVT), 183 patients were later diagnosed with cancer, of whom, 95 patients were diagnosed within 3 months of their SVT diagnosis. When compared to the general population, individuals diagnosed with SVT were 33 times more likely to be diagnosed with cancer within 3 months and their 3 month risk of developing cancer was 8%. The increased risk was for liver cancer, pancreatic cancer and myeloproliferative neoplasms and there was a continued twofold increase after one or more years of follow up. It was noted that Splanchnic Venous Thrombosis was also a poor prognostic factor for survival, in patients with liver and pancreatic cancer. The authors concluded that Splanchnic Venous Thrombosis (SVT) is a marker of occult malignancy, particularly liver cancer, pancreatic cancer and myeloproliferative neoplasms and SVT diagnosed in patients with liver or pancreatic cancer remains a poor prognostic factor. Therefore, patients presenting with Splanchnic Venous Thrombosis may require a more thorough diagnostic evaluation. Splanchnic venous thrombosis is a marker of cancer and a prognostic factor for cancer survival. Søgaard KK, Farkas DK, Pedersen L, et al. Blood, June 2015 DOI: 10.1182/blood-2015-03-631119