Evaluating Rivaroxaban for Thromboprophylaxis in Cancer Patients with Long-Term Venous Access Devices: A Retrospective Cohort Study.

Background: Long-term venous access devices, including PICCs and implantable ports, increase the risk of catheter-related thrombosis (CRT) in cancer patients. The role of prophylactic rivaroxaban in this setting remains uncertain. Methods: We retrospectively analyzed adult cancer patients who underwent peripherally inserted central catheter (PICC) or implantable port (PORT) placement between January 2019 and May 2023. CRT was diagnosed via B-ultrasound. To reduce surveillance bias, only patients who underwent ≥4 ultrasound examinations were included. Kaplan-Meier and Cox regression were used to assess the effect of rivaroxaban prophylaxis and to explore subgroup differences. Results: Among 1,585 patients with upper-limb catheters, 822 met inclusion criteria, with 135 CRT events. The median time to CRT was 55 days (IQR: 29.5-121.5), and 66.2% occurred within 90 days post-catheterization. Prophylactic rivaroxaban significantly reduced CRT risk (HR = 0.47, 95% CI: 0.33-0.67; p < 0.001), particularly in high-risk groups such as those with PICC lines or active tumors. No significant benefit was observed in patients with no-evidence-of-disease (NED) or those with cardiac stents, atrial fibrillation, or prior cerebral infarction. In the PORT subgroup, risk reduction was not statistically significant overall (HR = 0.66, p = 0.07), but became significant after excluding NED and cardiovascular conditions (HR = 0.52, p = 0.0195). Conclusion: Rivaroxaban prophylaxis reduces CRT in cancer patients with long term central venous catheters, particularly those with PICCs or active disease. Routine use appears unnecessary in NED or patients on antiplatelet therapy, highlighting the importance of individualized prophylaxis strategies.