Aim of the studyThromboprophylaxis in cancer patients during hospitalization reduces the risk of venous thromboembolism (VTE).Material and methodsTo assess the underuse and the overuse of thromboprophylaxis in cancer patients at a tertiary oncology department, we retrospectively analyzed 1983 consecutive hospitalizations of 498 cancer patients who received chemotherapy from October 2016 to May 2017. The Padua prediction score (≥ 4 points) and Caprini risk assessment (≥ 5 points) were used to identify patients at high risk of VTE.ResultsThe majority of individuals (n = 363, 72.9%) suffered from advanced lung cancer. We found that 419 (84.14%) patients received thromboprophylaxis with enoxaparin 40 mg qd,including 181 (43.2%) individuals using concomitant mechanical thromboprophylaxis. As few as 44 (8.8%) and 11 (2.2%) patients did not receive thromboprophylaxis despite high VTE risk based on the Caprini risk assessment and Padua prediction score, respectively (p < 0.001). The number of patients without high risk of VTE, who received pharmacological thromboprophylaxis, was higher when the Padua prediction score was used compared with the Caprini risk assessment (n = 391 [78.5%] vs. n = 210 [42.2%], respectively; p < 0.001). Three patients (0.6%) experienced vascular events during hospital stay, including one symptomatic deep vein thrombosis. No major bleeding was observed. Predictors of thromboprophylaxis overuse were as follows: previous VTE and abnormal pulmonary function for both scales.ConclusionsThis study shows that thromboprophylaxis in cancer in patients undergoing chemotherapy is suboptimal in Poland in part due to the use of various VTE risk scores yielding discrepant results in everyday practice.