Risk of venous thromboembolism in patients receiving adjuvant chemotherapy with 5-fluorouracil, epirubicin and cyclophosphamide for early breast cancer

Aim:   Previous studies have shown that adjuvant chemotherapy in early breast cancer (EBC) may increase the risk of venous thromboembolism (VTE). Clinical experience suggests the combination of 5-fluorouracil, epirubicin and cyclophosphamide (FEC) may be associated with a higher frequency of VTE than other regimens. This study aims to investigate the use of adjuvant FEC compared with other adjuvant regimens in the development of VTE in patients with EBC.
Methods:   A retrospective audit was conducted examining all eligible patients who received adjuvant chemotherapy for EBC in the Australian Capital Territory from 1 January 2005 to 30 June 2007. Data were collected from patients' notes, including risk factors for VTE, tumor pathology, chemotherapy details and incidence of VTE. Comparisons using χ² tests and independent samples t -tests were made between patients who received FEC and those who received another regimen. Multivariate logistic regression was used to investigate prognostic factors for the development of VTE.
Results:   A total of 325 patients were included in the study, of whom 176 received FEC and 149 received other adjuvant chemotherapy regimens. The incidence of VTE in patients who received FEC was 47/176 (27%), which was significantly higher than for patients who received other regimens (7/149, 5%, P  < 0.001). FEC was the only significant prognostic factor for the development of VTE (OR 7.9, 95% CI 3.3–19.2, P  < 0.001).
Conclusion:   The use of adjuvant FEC chemotherapy is associated with an increased incidence of VTE in patients with EBC compared with other commonly used chemotherapy regimens.