Association between Level of Tumor Markers and Development of VTE in Patients with Pancreatic, Colorectal and Ovarian Ca: Retrospective Case- Control Study in Two Community Hospitals.

The risk of venous thromboembolism (VTE) is increased in patients with cancer. However, the role of tumor markers as potential indicators of increased risk of VTE is still undetermined. In this retrospective observational case control study, levels of the tumor markers CEA, CA 19-9 and CA 125 in patients with colorectal, pancreatic, and ovarian cancer respectively, who were admitted to two community hospitals between January 2001 and December 2011, were compared between patients who were VTE positive and those who were VTE negative. The primary goal of this study was to determine whether VTE positive cancer patients had higher tumor marker levels compared to VTE negative cancer patients. In our study, 66.7% (48/72) of patients who were positive for VTE had elevated tumor markers while 65.3% (66/101) of patients who were negative for VTE had low (normal) tumor markers, indicating an association of high tumor marker levels with the diagnosis of VTE. This was statistically significant with an odds ratio of 3.77 and p-value of <0.0001 (95% CI of 1.99-7.14). When the VTE group was further divided into DVT and PE groups, 70.2% (40/57) of patients in the DVT positive group had high tumor markers with a p value of <0.0001 and an odds ratio of 3.99 (95% CI of 2.02 to 7.89) while 57.9% (11/19) of patients in pulmonary embolism positive group had high tumor markers; this was, however, not statistically significant (p-value of 0.35 and a CI of 0.59 to 4.10). In this retrospective study of 173 individuals with a diagnosis of either colorectal, pancreatic, or ovarian Cancer, higher tumor marker levels (CEA, CA 19-9, and CA 125 respectively) were associated with an increased risk of VTE, either DVT or PE. However, when further divided into either DVT or PE groups, the association remained statistically significant only for DVT but not for PE.