Postoperative Venous Thromboembolism Predicts Survival in Cancer Patients

Abstract
Objectives: To determine whether a postoperative venous thromboembolism (VTE) is associated with a worse prognosis and/or a more advanced cancer stage and to evaluate the association between a postoperative VTE and cancer-specific survival when known prognostic factors, such as age, stage, cancer type, and type of surgery, are controlled. Context: It is unknown whether oncology patients who develop a venous thromboembolism after a complete curative resection are at the same survival disadvantage as oncology patients with a spontaneous VTE. Methods: A retrospective case control study was conducted at Memorial Sloan-Kettering Cancer Center. Years of study: January 1, 2000, to December 31, 2005. Median follow-up: 24.9 months (Interquartile range 13.0, 43.0). All cancer patients who underwent abdominal, pelvic, thoracic, or soft tissue procedures and those who developed a VTE within 30 days of the procedure were identified from a prospective morbidity and mortality database. Overall survival (OS) was calculated for the entire cohort. In the matched cohort, OS and disease-specific survival (DSS) were calculated for stages 0 to 3 and stages 0 to 2. Results: A total of 23,541 cancer patients underwent an invasive procedure and 474 (2%) had a postoperative VTE. VTE patients had a significantly worse 5-year OS compared to no-VTE patients (43.8% vs 61.2%; P < 0.0001); 205 VTE patients (stages 0–3) were matched to 2050 controls by age, sex, cancer type, stage, and surgical procedure. In this matched analysis, VTE patients continued to demonstrate a significantly worse prognosis with an inferior 5-year OS (54.7% vs 66.3%; P < 0.0001) and DSS (67.8% vs 79.5%; P = 0.0007) as compared to controls. The survival difference persisted in early stage disease (stage 0–2), with 5-year DSS of 82.9% versus 87.3% (P = 0.01). Conclusions: Postoperative VTE in oncology patients with limited disease and a complete surgical resection is associated with an inferior cancer survival. A postoperative VTE remains a poor prognostic factor, even when controlling for age, stage, cancer type, and surgical procedure further supporting an independent link between hypercoagulability and cancer survival.