Objectives The purpose of this study is to determine the incidence of venous thromboembolism (VTE) in patients with ovarian cancer receiving neoadjuvant chemotherapy (NACT), to determine the effect of VTE on overall survival, and identify risk factors of VTE in patients receiving NACT.

Methods This is a retrospective cohort study of patients diagnosed with primary ovarian/fallopian tube/peritoneal cancer and treated with NACT between June 2013 to June 2016. The primary outcome was incidence of VTE during NACT. The secondary outcomes were risk factors for VTE and overall survival. Demographic data, histology, stage, chemotherapy treatment, and incidence of VTE were collected. Statistical analysis included Kaplan-Meier estimates, and univariate and multivariate Cox regression analysis.

Results 284 patients were included in the study. The average age at diagnosis was 63.8 years old. The incidence of VTE during NACT was 13.3%. The median overall survival for the study population was 25.23 months. Kaplan-Meier estimates demonstrate a decrease in overall survival in patients who had a VTE during NACT (14.98 months, 95% CI 14.48 – 16.49) compared to patients who did not (26.81 months, 95% CI 22.76 – 30.86) p < 0.0001. Multivariate analysis identified albumin < 35 (HR 2.56), BMI > 30 (HR 2.48), and serous histology (HR 2.90) as risk factors for VTE during NACT.

Conclusion Patients with ovarian cancer receiving NACT are at an increased risk of VTE, which is associated with a shorter overall survival. These findings suggest that thromboprophylaxis may have a role in this patient population.