The therapeutic landscape of cancer-associated splanchnic vein thrombosis

Splanchnic vein thrombosis (SVT), including portal, splenic, and mesenteric vein thrombosis and the Budd–Chiari syndrome, is an uncommon manifestation of venous thromboembolism frequently associated with solid abdominal malignancies and myeloproliferative neoplasms (MPNs). The management of cancer-associated SVT is challenging due to heterogeneous clinical presentations, competing risks of thrombosis and bleeding, and the lack of high-quality clinical studies in this setting. Based on available evidence, anticoagulation is associated with higher rates of recanalization in patients with solid cancer, with no impact on the mortality rates and a non-negligible bleeding risk. Most available data derive from observational studies, with low-molecular-weight heparin (LMWH) historically representing the most frequently used anticoagulant, although direct oral anticoagulants (DOACs) are increasingly prescribed following evidence from cancer-associated thrombosis in usual sites. In MPN-associated SVT, anticoagulation is generally recommended indefinitely in combination with cytoreductive therapy. Available cohort studies suggest comparable outcomes among vitamin K antagonists (VKAs), LMWH, and DOACs, but robust comparative data are lacking. Overall, current evidence supports an individualized, risk-adapted anticoagulant approach in patients with cancer-associated SVT.