Incidence of venous thromboembolism in patients with advanced staged ovarian cancer undergoing neoadjuvant chemotherapy (411)

Abstract

<b>Objectives:</b> Venous thromboembolism (VTE) during neoadjuvant chemotherapy (NACT) treatment for epithelial ovarian cancer (EOC) can delay interval debulking surgery (IDS) and affect overall prognosis. Our primary objective was to determine the incidence and timing of VTEs in patients with advanced-stage EOC who received NACT. Our secondary aims were to identify specific risk factors that increase the risk of VTE and assess the rate of direct-acting oral anticoagulants (DOACs) use for VTE treatment. <b>Methods:</b> Our retrospective cohort study included patients with stage IIIC/IV EOC who received NACT followed by IDS between January 2, 2012, and April 30, 2018, at a single institution. Patients were identified from a prospectively maintained surgical database of clinical, surgical, and outcomes data collected from the medical record. Medical records were reviewed to ascertain a prior history of VTE or the date of a clinical diagnosis of VTE between the EOC diagnosis and up to 180 days after IDS. VTE was defined as a deep vein thrombosis and/or pulmonary embolism diagnosed by Doppler ultrasound or computed tomography angiogram, respectively. Associations of patient characteristics with the development of VTE between EOC diagnosis and IDS were evaluated univariately using logistic regression. <b>Results:</b> Of the 160 patients who met the study inclusion criteria, five patients had a remote history of VTE prior to EOC diagnosis, and four had a concurrent VTE at time of diagnosis and thus were excluded from the analyses. Among the remaining 151 patients (mean age: 65.7 years), there were 29 (19.2%) incident cases of VTE between EOC diagnosis and the first 180 days after IDS: nine (6.0%) between EOC diagnosis and start of NACT, 13 (8.6%) during NACT and before IDS, and seven (4.6%) occurred within 180 days after IDS (Figure). Among these 29 patients, ten (34.5%) received a DOAC, specifically apixaban and rivaroxaban, for VTE treatment without complications. We were unable to identify any statistically significant associations between the following factors and the occurrence of VTE between EOC diagnosis and IDS: age, body mass index, smoking status, American Society of Anesthesiologists (ASA) score (>3 vs <3: odds ratio [OR]: 2.3, 95% CI: 0.7-7.2), Khorana score, and clinical tumor histology (non-serous vs serous: OR: 2.9, 95% CI: 0.7-12.4), or stage (IV vs IIIC: OR: 1.5, 95% CI: 0.6-3.8). <b>Conclusions:</b> Of the patients with advanced EOC who underwent NACT, 14.6% experienced a possible preventable VTE between EOC diagnosis and IDS. VTE during NACT can significantly delay IDS and affect the overall prognosis. Our results raise the need for further research to determine the population of patients who would benefit from thromboprophylaxis during NACT. The use of DOAC may be safe in this patient population.