Risk of venous thromboembolism in ovarian cancer patients receiving neoadjuvant chemotherapy

Purpose To determine the incidence of venous thromboembolism (VTE) and define clinical risk factors associated with the development of new-onset VTE in patients receiving neoadjuvant chemotherapy (NACT) for ovarian cancer (OC). Methods An institutional ovarian cancer database was used to identify all OC patients receiving NACT from 04/2015–09/2018. VTE events were recorded and included clinically diagnosed deep venous thrombosis (DVT) and/or pulmonary embolism (PE). The incidence of VTE events was categorized according to treatment phases (P): P0) First visit/prior to induction of NACT; P1) during NACT before interval debulking surgery (IDS); P2) intraoperative through day 28 post-IDS; P3) during adjuvant chemotherapy. Results A total of 290 patients were identified during the study period. Seventy-five (25.9%) developed a VTE at some point from time of presentation through the peri-operative period. Forty (13.8%) presented with VTE prior to initiation of NACT. An additional 27 (11.6%) developed a VTE during NACT (P1); 6 (3.9%) during the intraoperative and 28-day post-operative period (P2); and 2 (1.3%) during the adjuvant period (P3). The overall VTE rate was 25.9% (n = 75). FIGO stage IV disease was the only factor associated with increased risk for a new-onset VTE [Odds Ratio (OR): 3.9 (95% Confidence Interval [CI] = 1.2–13.6; p = 0.03]. Conclusions Patients receiving NACT for advanced OC are at extremely high risk for developing thromboembolic events, either at initial presentation or during induction of NACT, a treatment phase that is traditionally without use of prophylactic anticoagulation. Since Khorana scoring is not predictive in this population, clinicians might need to consider increased screening or use of prophylactic anticoagulation in patients receiving NACT for OC, particularly in advanced metastatic disease.