PB0394 - Prevalence of symptomatic venous thromboembolism (VTE) after surgery for gynecologic malignancy

Background: Postoperative thromboprophylaxis in patients with gynecologic cancer is suggested in many guidelines. However, in Thailand, most gynecologists do not apply these guidelines in practice because of a belief of very low prevalence of postoperative venous thromboembolism (VTE) and concern of bleeding related to thromboprophylaxis. Data of postoperative VTE burden in Thai gynecologic cancer patients are scant.

Aims: To evaluate the prevalence of symptomatic VTE (deep vein thrombosis and pulmonary embolism) and an association between Caprini risk assessment model (RAM), a tool for assessing the risk of VTE, and symptomatic VTE in postoperative gynecologic cancer patients at Siriraj hospital.

Methods: Retrospective chart review on 660 gynecologic cancer patients (mean age of 54 years) who underwent surgery from March 2018 to October 2019 was conducted. Exclusion criteria included recent VTE within 30 days before admission, receiving therapeutic dose of anticoagulant before surgery or at 48-72 hour post-operation. Data regarding cancer, operation, Caprini risk score, thromboprophylaxis, and symptomatic VTE were assessed.

Results: The common sites of cancer included endometrium (42.0%), ovary (31.8%), exocervix (8.0%) and endocervix (4.4%). Open laparotomy was more common than laparoscopic surgery (90% vs.10%). Mechanical and pharmacological thromboprophylaxis was used in 2.6% and 5.0%, respectively. Median Caprini score was 7 (range, 4 to 13). The prevalence of symptomatic VTE in postoperative gynecologic cancer patients within 90 days was 1.06% (95%CI: 0.43-2.17). Total Caprini risk score was not significantly associated with symptomatic VTE. In multivariate analysis, among Caprini risk assessment factors, only serious infection (within 1 month) showed a statistically significant association with symptomatic VTE (p-value= 0.003).

Conclusion(s): The prevalence of symptomatic VTE after gynecologic cancer surgery without thromboprophylaxis among Thai patients was low. Caprini RAM cannot predict postoperative VTE. Recent serious infection was associated with symptomatic VTE.