Julia Rose Salinaro

Incidence of venous thromboembolism among patients receiving neoadjuvant chemotherapy for advanced epithelial ovarian cancer

Neoadjuvant chemotherapy may be considered for women with epithelial ovarian cancer who have poor performance status or a disease burden not amenable to primary cytoreductive surgery. Overlap exists between indications for neoadjuvant chemotherapy and known risk factors for venous thromboembolism, including impaired mobility, increasing age, and advanced malignancy. The objective of this study was to determine the rate of venous thromboembolism among women receiving neoadjuvant chemotherapy for epithelial ovarian cancer. A multi-institutional, observational study of patients receiving neoadjuvant chemotherapy for primary epithelial ovarian, fallopian tube, or peritoneal cancer was conducted. Primary outcome was rate of venous thromboembolism during neoadjuvant chemotherapy. Secondary outcomes included rates of venous thromboembolism at other stages of treatment (diagnosis, following interval debulking surgery, during adjuvant chemotherapy, or during treatment for recurrence) and associations between occurrence of venous thromboembolism during neoadjuvant chemotherapy, subject characteristics, and interval debulking outcomes. Venous thromboembolism was defined as deep vein thrombosis in the upper or lower extremities or in association with peripherally inserted central catheters or ports, pulmonary embolism, or concurrent deep vein thrombosis and pulmonary embolism. Both symptomatic and asymptomatic venous thromboembolism were reported. A total of 230 patients receiving neoadjuvant chemotherapy were included; 63 (27%) patients overall experienced a venous thromboembolism. The primary outcome of venous thromboembolism during neoadjuvant chemotherapy occurred in 16 (7.7%) patients. Of the remaining venous thromboembolism events, 22 were at diagnosis (9.6%), six post-operatively (3%), five during adjuvant chemotherapy (3%), and 14 during treatment for recurrence (12%). Patients experiencing a venous thromboembolism during neoadjuvant chemotherapy had a longer mean time to interval debulking and were less likely to undergo optimal cytoreduction (50% vs 80.2%, p=0.02). Patients with advanced ovarian cancer are at high risk for venous thromboembolism while receiving neoadjuvant chemotherapy. Consideration of thromboprophylaxis may be warranted.

Cost-Effectiveness of Venous Thromboembolism Prophylaxis During Neoadjuvant Chemotherapy for Ovarian Cancer

PURPOSE: Two recent clinical trials have demonstrated that direct oral anticoagulants (DOACs) are effective as venous thromboembolism (VTE) prophylaxis in patients with moderate-to-high risk ambulatory cancer initiating chemotherapy. Patients with advanced ovarian cancer receiving neoadjuvant chemotherapy are at particularly increased risk of VTE. We performed a cost-effectiveness analysis from a health system perspective to determine if DOACs are a feasible prophylactic strategy in this population. METHODS: A simple decision tree was created from a health system perspective, comparing two strategies: prophylactic DOAC taken for 18 weeks during chemotherapy versus no VTE prophylaxis. Rates of VTE (7.3% DOAC v 13.6% no treatment), major bleeding (2.6% v 1.3%), and clinically relevant nonmajor bleeding (4.6% v 3.3%) were modeled. Cost estimates were obtained from wholesale drug costs, published studies, and Medicare reimbursement data. Probabilistic, one-way, and two-way sensitivity analyses were performed. RESULTS: In the base case model, DOAC prophylaxis is more costly and more effective than no therapy (incremental cost-effectiveness ratio = $256,218 in US dollars/quality-adjusted life year). In one-way sensitivity analyses, reducing the DOAC cost by 32% or raising the baseline VTE rate above 18% renders this strategy potentially cost-effective with an incremental cost-effectiveness ratio below $150,000 in US dollars/quality-adjusted life year. CONCLUSION: Further confirmation of the true baseline VTE rate among women initiating neoadjuvant chemotherapy for ovarian cancer will determine whether prophylactic dose DOAC is a value-based strategy. Less costly VTE prophylaxis options such as generic DOACs (once available) and aspirin also warrant investigation.

Aspirin for Prevention of Venous Thromboembolism Among Ovarian Cancer Patients Receiving Neoadjuvant Chemotherapy

This is a pilot study to determine the safety and efficacy of low dose aspirin for the prevention of venous thromboembolism among women with advanced ovarian cancer receiving neoadjuvant chemotherapy.