Use of high white blood cell (WBC) count to predict poor survival outcome in gastrointestinal (GI) cancer with thrombotic event

e19614 Background: There are some known risk factors for deep vein thrombosis in cancer patients, such as primary site of cancer, white blood cell count (WBC), hemoglobin (Hb), platelet count (PLT). We investigated the association between these factors and the overall survival as prognostic factor in gastrointestinal (GI) cancer patients. Methods: All the patients with gastrointestinal cancer, who developed deep vein thrombosis or pulmonary thromboembolism through the clinical course, were retrospectively reviewed between January 2009 and June 2011 at Seoul St. Mary’s Hospital. According to treatment, patients were classified into two groups; the chemotherapy group and the supportive care group. Results: Of the fifty-six patients, median age was sixty three year-old. Stomach cancer was most common 35% , pancreatic cancer 31%, colorectal cancer 19%, and biliary cancer was 15%. There were three pattern of thrombosis: 19 (34%) deep vein thrombosis (DVT) only, 12 (21%) pulmonary thromboembolism (PTE) only, 25 (45%) combined DVT with PTE. WBC count above 11,000/µ° showed the poor overall survival than other group (median survival 3.4 months vs. 1.7 months, respectively, p=0.015) However, other risk factor did not show any significant association (Hb: p=0.521, PLT: p=0.295) In chemotherapy group, twelve (55%) patients had progressive disease and ten (45%) patients had stable disease at the time of thrombotic event. There was no statistically significant association between thrombosis and tumor response. The chemotherapy group had tendency of better survival outcome than the supportive care group without statistical significance (median survival 2.4 months vs. 5.3months, p=0.07). Conclusions: In GI cancer patients, elevated white blood cell count above 11,000/µ° can be important prognostic and risk factor for thrombosis with poor survival outcome. And the response of chemotherapy seemed to have no influence on thrombotic event during chemotherapy. This is very limited study due to small sample size and retrospective analysis, and heterogenous type of cancer. Further large study should be warranted to define the thrombotic risk factor as prognostic marker.