Abstract:

Cancer-associated thrombosis (CAT) is the second leading cause of death in cancer patients, second only to the progression of the tumor. It leads to extended hospitalization and re-hospitalization, resulting in a serious social medical burden. Tumor-specific gene mutations such as JAK2, ALK, and KRAS mutations are closely related to the risk of CAT in patients with solid tumors. Patients treated with immune checkpoint inhibitors have a high risk of CAT, with a 1-year cumulative incidence rate of 10.86%. Therefore, accurate risk assessment is important. The Khorana risk score (KRS) is the first model to assess CAT risk and has been validated in several studies. The new generation models are based on the improvement of KRS, but they have not yet undergone large-scale external verification, such as the Vienna CAT model, PROTECHT model, and CONKO model. Due to the strong correlation between tumors and CAT, several CAT-related prevention guidelines have been established domestically and abroad. All of these guidelines recommend that patients undergo preventive anticoagulation therapy after tumor surgery. Low molecular weight heparin (LMWH) is the most widely used anticoagulant drug to prevent CAT. New oral anticoagulants (NOAC) are also used to prevent CAT, despite the incidence of hemorrhaging increases, the overall benefits to patients outweigh the risks. The strategy for treating CAT is complex. For patients with non-gastrointestinal tumors, NOAC can be used as a first-line drug, while LMWH is recommended for anticoagulation in patients with gastrointestinal tumors. Since CAT patients receive anticoagulation and anti-tumor therapy at the same time, drug interactions need to be considered to avoid drug-induced bleeding, especially the impact of combined medication on NOAC pharmacokinetics. The ideal length of anticoagulation therapy for CAT remains unclear. Guidelines recommend that patients with CAT should indefinitely continue the anticoagulation therapy after completing 3 to 6 months of initial anticoagulation therapy. Therefore, when determining the course of anticoagulation therapy for cancer patients, physicians should evaluate the risk of recurrence of thrombosis and bleeding, and optimize the treatment plan.

Key words: Cancer, Venous thromboembolism, Prophylaxis, Treatment