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Background Low‐molecular‐weight heparin has been the preferred treatment of cancer‐associated thrombosis (CAT); however, emerging data support the use of direct oral anticoagulants (DOACs). Objectives The Memorial Sloan Kettering Cancer Center Clinical Pathway has served as the institutional guideline for the use of rivaroxaban to treat CAT since 2014. Key elements are to recommend against use of a DOAC in patients with active gastrointestinal (GI) or genitourinary tract lesions, and a prespecified dose reduction in the elderly (75+ years old). We present our institutional experience for treatment of CAT. Methods From January 2014 through September 2016, 1072 patients began rivaroxaban treatment for CAT; 91.9% had a solid tumor, 8.1% had hematologic malignancies, and 75% of patients with solid tumors had metastatic disease. All patients with CAT treated with rivaroxaban were included in this analysis, regardless of adherence to the Clinical Pathway. Results The 6‐month cumulative incidence of recurrent venous thromboembolism and major bleeding were 4.2% (95% confidence interval [CI], 2.7%‐5.7%) and 2.2% (95% CI, 1.1%‐3.2%), respectively. The incidence of clinically relevant non–major bleeding leading to discontinuation of rivaroxaban for at least 7 days was 5.5% (95% CI, 3.7%‐7.1%), and 73.3% of major bleeds occurred in the GI tract. The 6‐month cumulative mortality rate was 22.2% (95% CI, 19.4%‐24.9%). The elderly had similar rates of recurrent thrombosis and bleeding as those aged under 75 years. Conclusion Our institutional experience suggests that in appropriately selected patients, rivaroxaban may be used for treatment of CAT with promising safety and efficacy.

Chemotherapy-induced thrombocytopenia (CIT) is common during treatment with antineoplastic therapies and may adversely impact chemotherapy dose intensity. There is no approved therapy for CIT. In our recent phase II randomized study, romiplostim led to correction of platelet counts in 85% of treated patients and allowed resumption of chemotherapy, with low rates of recurrent CIT in the first two cycles or 8 weeks of chemotherapy. However, there is a lack of long-term data on the efficacy and safety of romiplostim in CIT.To analyze efficacy and safety of romiplostim in the patients in the phase 2 study, who received romiplostim for ≥1 year.Twenty-one patients remained on romiplostim for ≥1 year. We analyzed the effect of romiplostim on platelet counts, absolute neutrophil counts, and hemoglobin, as well as impact on ongoing chemotherapy. We also tracked venous or arterial thrombotic events.During the study period, romiplostim was effective in preventing reduction of chemotherapy dose intensity due to CIT. Fourteen of the 20 (70%) analyzable patients experienced no episode of CIT, 4 subjects experienced a single chemotherapy dose delay due CIT, and 2 patients required a chemotherapy dose reduction. Platelet counts were preserved throughout the duration of the extension analysis. One patient experienced a proximal deep vein thrombosis, and one patient experienced multiple tumor-related ischemic events.Long-term use of romiplostim for treatment of CIT was effective and safe, with no evidence of resistance or increased risk of thrombosis.

Background Prophylactic anticoagulation with rivaroxaban significantly reduced the risk of cancer-associated thrombosis during the intervention period in the CASSINI trial. Direct oral anticoagulants may increase the risk of gastrointestinal (GI) tract bleeding in patients with an in situ GI tract cancer or lesion. Objective This post hoc analysis characterized the efficacy and safety of rivaroxaban in patients with and without gastric/gastroesophageal junction (G/GEJ) tumors. Methods Primary and secondary efficacy end points and adjudicated bleeding events, including bleeding sites, were analyzed for the intent-to-treat population by cancer type (G/GEJ vs non-G/GEJ) for the 180-day observation period. Results In patients with G/GEJ tumors, the rates for the primary efficacy end point were 3.4% for rivaroxaban versus 6.9% for placebo (hazard ratio [HR], 0.45; 95% confidence interval [CI], 0.11-1.80). In patients with non-G/GEJ tumors, the rivaroxaban group had a lower risk of the primary end point (6.6% vs 9.3%; HR, 0.70; 95% CI, 0.40-1.21). Rates of major bleeding in patients with G/GEJ tumors were 4.6% (4/88) versus 1.2% (1/85) for rivaroxaban and placebo; rates in patients with non-G/GEJ tumors were 1.3% (4/317) versus 0.9% (3/319), respectively. Conclusions Excluding patients with G/GEJ tumors resulted in a definable population of cancer patients who achieved an improved benefit-risk balance from rivaroxaban prophylaxis.