Background: Little is known about the epidemiology of venous thromboembolism in hospitalized patients in Israel. Also, a direct comparison of the clinical and laboratory features between cancer and non-cancer patients has not yet been reported.
Objectives: To investigate and compare the epidemiologic, clinical and laboratory characteristics of cancer and non-cancer patients hospitalized with venous thromboembolism in a large referral medical center in Israel.
Methods: Between February 2002 and February 2003, patients diagnosed at the Rambam Medical Center as suffering from VTE (deep vein thrombosis and/or pulmonary embolism), based on diagnostic findings on Doppler ultrasonography, spiral computed tomography scan or lung scan showing high probability for pulmonary embolism, were prospectively identified and evaluated. In addition, at the conclusion of the study period, the reports of spiral chest CT scans, performed during the aforementioned period in this hospital, were retrospectively reviewed to minimize the number of unidentified cases. Blood samples were drawn for evaluation of the coagulation profile.
Results: Altogether, 147 patients were identified and 153 VTE events diagnosed, accounting for 0.25% of all hospitalizations during the study period. The cancer group included 63 patients (43%), most of whom had advanced disease (63%). The most common malignancies were cancer of the lung (16%), breast (14%), colon (11%) and pancreas (10%). Of 121 venous thromboembolic events (with or without pulmonary embolism) there were 14 upper extremity thromboses (12%). The most common risk factors for VTE, except malignancy, were immobilization (33%), surgery/trauma (20%) and congestive heart failure (17%). There was no difference in prevalence of various risk factors between cancer and non-cancer patients. During an acute VTE event, D-dimer levels were higher in cancer patients than non-cancer patients (4.04 ± 4.27 vs. 2.58 ± 1.83 mg/L respectively, P = 0.0550). Relatively low values of activated protein C sensitivity ratio and normalized protein C activation time were observed in both cancer and non-cancer groups (2.05 ± 0.23 vs. 2.01 ± 0.33 and 0.75 ± 0.17vs. 0.71 ± 0.22, respectively). These values did not differ significantly between the groups.
Conclusion: The proportion of cancer patients among patients suffering from VTE was high. Their demographic, clinical and laboratory characteristics (during an acute event) were not different from those of non-cancer patients, except for higher D-dimer levels.