Cancer-Associated Abdominal Vein Thrombosis

SIMPLE SUMMARY: Cancer is associated with a high risk of developing venous thromboembolism, which includes thrombosis in unusual areas such as the abdominal veins (splanchnic, ovarian and renal veins). These thromboses are often incidental findings in the workup of a cancer patient. Cancer is one of the major risk factors for splanchnic vein thrombosis, ovarian vein thrombosis and renal vein thrombosis. Cancer-associated abdominal vein thrombosis carries high mortality rates and high risk of recurrent thrombosis. The management of cancer-associated abdominal vein thrombosis follows the general guidelines for the management of venous thromboembolism. ABSTRACT: Cancer is associated with an increased risk of developing venous thromboembolism, due to its direct influence on the three pillars of Virchow’s triad (e.g., compression on the blood vessels by the tumour, blood vessels invasion, and cytokine release), together with the effect of exogenous factors (such as chemotherapy, radiotherapy, surgery). In cancer patients, the risk of thrombosis at unusual sites, such as splanchnic, ovarian and renal vein thrombosis, is also increased. Abdominal vein thromboses are frequently incidental findings on abdominal imaging performed as part of the diagnostic/staging workup or the follow-up care of malignancies. There is little evidence on the management of unusual site venous thromboembolism in cancer patients since there are only a few specific recommendations; thus, the management follows the general principles of the treatment of cancer-associated deep vein thrombosis and pulmonary embolism. This narrative review summarises the latest evidence on cancer-associated abdominal vein thrombosis, i.e., thrombosis of the splanchnic, ovarian and renal veins.