e22217 Background: There are many ongoing researchs for novel prognostic factors in colorectal cancers. Increased thromboembolic events were associated with poor prognosis and survival in cancer patients. Thrombin-activated fibrinolysis inhibitor (TAFI), which has inhibitory effects on fibrinolysis, was proven to play a major role in hypercoagulopathy and was reported to reach high blood levels in cancer patients compared to those in the general population. Methods: TAFI levels were measured. The correlation between those levels and clinicopathologic features were analyzed in 82 patients with advanced stage colorectal cancer receiving treatment in our clinic. Results: Eighty-two patients were evaluated. Patients characteristics included 54 males (65.9%), 28 females (34.1%); median age 56.4 (range:24–76). The mean TAFI levels was 198,36±70,01 Ğer yazali and TAFI levels were found to be high in 70% of patients. High levels of TAFI were more common in rectum cancer patients compared with colon cancer patients. There was no significant correlation between TAFI levels and clinicopathologic factors, such as age, sex, body mass index, performance status, number of metastases, grade, vascular invasion, perineural invasion and CEA levels. The TAFI levels of patients receiving bevacizumab (202.1±66.6) were more higher than those no receiving (191,83±76,21), but this association was not statistically significant (p>0.05). Conclusions: Although the statistical analysis proved insignificant in our study, the effect of thromboembolic events on prognosis and survival is well established. Thus, large scale prospective studies are required to determine prognostic factors. No significant financial relationships to disclose.