Association of chemotherapy regimen with venous thromboembolic risk in patients with urothelial tract cancer.

Abstract

314 Background: Cisplatin chemotherapy (CTX) is associated with increased risk of venous thromboembolism (VTE); however, other agents have also been hypothesized to increase risk. We assessed the association of VTE with different CTX regimens in urothelial tract cancer patients. Methods: We identified > 66 year-old patients diagnosed with urothelial tract cancers (excluding renal pelvis) from the Surveillance, Epidemiology, and End Results (SEER) Medicare-linked database from 1998 to 2011. CTX regimens included gemcitabine/cisplatin (GC), methotrexate/vinblastine/doxorubicin/cisplatin (MVAC), or gemcitabine/carboplatin (GCarbo). We calculated VTE rates within 120 days of CTX initiation and compared VTE by CTX regimen with multivariable logistic regression models adjusted for patient and cancer characteristics. Results: Of 5050 identified patients, VTE occurred in 13.1% (660/5050). VTE rates were 15.3% (265/1737) and highest for GC; 8.8% (23/262) and 12.2% (372/3051) of MVAC and GCarbo patients experienced VTE, respectively. Adjusted for patient demographic and cancer-specific variables, MVAC and GCarbo were associated with lower odds of VTE compared with GC (see Table). Conclusions: Compared with GC, MVAC and GCarbo are associated with a decreased rate of VTE. This finding suggests that gemcitabine may add to the increased thrombosis risk from cisplatin. Patients treated with GC should be counseled about this association. Sensitivity analyses to assess VTE risk of different CTX regimens in the perioperative setting will be presented. [Table: see text]