Mirjana Kovac1, Zeljko Kovac2, Zorica Tomasevic3, Slavko Vucicevic4, Valentina Djordjevic5, Iva Pruner6, Dragica Radojkovic7. 1. Faculty of Medicine, University of Belgrade, Serbia; Blood Transfusion Institute of Serbia, Hemostasis Department, Belgrade, Serbia. Electronic address: mkovac008@gmail.com. 2. National Cancer Research Institute, Serbia. Electronic address: zeljko.kovac.2010@gmail.com. 3. National Cancer Research Institute, Serbia. Electronic address: zoricant@ncrs.ac.rs. 4. National Cancer Research Institute, Serbia. Electronic address: slafimi@gmail.com. 5. Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia. Electronic address: pq20210a@gmail.com. 6. Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia. Electronic address: iva.pruner@gmail.com. 7. Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia. Electronic address: dragica.radojkovic@gmail.com.
Abstract
BACKGROUND: Estimates of the risk ratio of tamoxifen-associated venous thromboembolism (VTE) in breast cancer patients range from 2.4 to 7.1. The occurrence of thrombosis in patients with breast cancer complicates the clinical condition and causes a change of treatment. Our study was conducted in order to investigate the influence of patient-related risk factors for thrombosis development in breast cancer patients whose treatment included adjuvant tamoxifen. METHODS: The prospective, single center, case control study included 150 breast cancer women, 50 whom developed venous thrombosis during adjuvant tamoxifen and 100 whom did not have thrombosis, as a control group. Patient-related risk factors such as: age, body mass index, previous VTE, varicose veins, concomitant diseases, the presence of prothrombotic mutations (FV Leiden, FII G20210A) and FVIII activity were evaluated in both groups. RESULTS: In respect of prothrombotic mutations, the FV Leiden mutation was present in a higher number of women from the VTE group (10/50 vs 7/100; P=0.020). Additionally, FVIII activity was significantly higher in the VTE group; median (IQR), of 1.79 (0.69) vs 1.45 (0.55); P<0.001 and more women in this group (24/50 vs 34/100) had increased FVIII activity; P=0.020. In those women with FVIII>1.5IU/ml, who were carriers of prothrombotic mutations, an OR of 3.76 (CI 95% 1.276-11.096; P=0.016) was obtained for VTE. CONCLUSION: The results of our study showed that the factor V Leiden mutation and high FVIII are associated with an increased risk of VTE in women with breast cancer during adjuvant tamoxifen.
BACKGROUND: Estimates of the risk ratio of tamoxifen-associated venous thromboembolism (VTE) in breast cancerpatients range from 2.4 to 7.1. The occurrence of thrombosis in patients with breast cancer complicates the clinical condition and causes a change of treatment. Our study was conducted in order to investigate the influence of patient-related risk factors for thrombosis development in breast cancerpatients whose treatment included adjuvant tamoxifen. METHODS: The prospective, single center, case control study included 150 breast cancerwomen, 50 whom developed venous thrombosis during adjuvant tamoxifen and 100 whom did not have thrombosis, as a control group. Patient-related risk factors such as: age, body mass index, previous VTE, varicose veins, concomitant diseases, the presence of prothrombotic mutations (FV Leiden, FII G20210A) and FVIII activity were evaluated in both groups. RESULTS: In respect of prothrombotic mutations, the FV Leiden mutation was present in a higher number of women from the VTE group (10/50 vs 7/100; P=0.020). Additionally, FVIII activity was significantly higher in the VTE group; median (IQR), of 1.79 (0.69) vs 1.45 (0.55); P<0.001 and more women in this group (24/50 vs 34/100) had increased FVIII activity; P=0.020. In those women with FVIII>1.5IU/ml, who were carriers of prothrombotic mutations, an OR of 3.76 (CI 95% 1.276-11.096; P=0.016) was obtained for VTE. CONCLUSION: The results of our study showed that the factor V Leiden mutation and high FVIII are associated with an increased risk of VTE in women with breast cancer during adjuvant tamoxifen.