The aim of this study was to define the incidence and prognostic significance of venous thromboembolism (VTE) in patients with advanced, epithelial ovarian cancer undergoing frontline adjuvant chemotherapy after an extended period (28 days) of postoperative prophylaxis.
A retrospective analysis of patients with advanced, epithelial ovarian cancer who underwent surgery and chemotherapy at a single institution from January 2008 through December 2011 was performed. Exclusion criteria were history of VTE, VTE during the postoperative period, clear cell histology, use of anticoagulation for a different indication, and lack of compliance with 28 days of postoperative prophylaxis with a low-molecular-weight heparin. Baseline patient demographics and oncologic outcomes were analyzed. Clinically symptomatic VTE was identified and confirmed with imaging studies. Otherwise, VTE was identified on imaging studies done to assess disease status at the conclusion of adjuvant chemotherapy.
One hundred twenty-eight patients met criteria for inclusion. Sixteen patients had a reported VTE during the time they were on frontline chemotherapy (12.5%). Nine patients (7%) had a pulmonary embolus, and 8 (6.3%) had a deep vein thrombus. The mean BMI in the group that developed VTE was 28, and in the group without VTE, it was 26.5 (P = 0.23). Three (23%) of the 16 patients who developed VTE had undergone a suboptimal cytoreduction compared with 12 (11%) of the 112 in the group with no VTE (P = 0.4). Six (37%) of the 16 patients who developed VTE during chemotherapy underwent a bowel resection and/or splenectomy during their cytoreductive surgery compared with 18 (16%) of the 112 patients who did not develop VTE (P = 0.079). Eight of the patients in the VTE group had indwelling venous catheters during chemotherapy (50%) compared with 39 (35%) in the group with no VTE (P = 0.27). In the group that developed VTE, there was a trend toward increased preoperative CA-125, higher rates of bowel resection and/or splenectomy during surgery, decreased use of aspirin, and inferior survival. On multivariate analysis, patients who developed VTE had significantly longer postoperative hospital stays (7 vs 5 days [P = 0.009]) and lower rates of complete response (P = 0.01).
A 12.5% risk for VTE merits consideration of prophylaxis during chemotherapy in this cohort. A randomized, controlled trial is needed to clarify whether the benefits of long-term prophylaxis outweigh the risks and costs of such therapy.