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.