Khorana risk score: Is the body mass index a predictable factor for thromboembolism in European countries? A retrospective analysis

e19612 Background: Five variables (site of cancer, platelet count, haemoglobin level, leukocyte count, and body mass index-BMI) define the Khorana risk score (KS), predicting the high (≥ 3), the moderate (1-2) and the low (0) risk of thromboembolic events (TEs) in cancer outpatients. Nadroparin has been demonstrated to reduce the incidence of TEs by about 50% in cancer outpatients receiving chemotherapy (PROTECHT study) and patients receiving chemotherapy including gemcitabine, platinum analogues or their combination are at higher risk of TEs. Methods: 378 patients enrolled in the PROTECHT study didn’t receive thromboprophylaxis (placebo group) and were evaluable for the KS. The aim of this retrospective analysis was to assess the distribution of the five KS variables and if the replacing of BMI variable, in the KS, with a chemotherapy variable (administration of platinum compound or gemcitabine added 1point and their association 2points) in a PROTECHT score (PrS) could better predict high risk patients. A receiver operating characteristic (ROC) curve has been used to assess the accuracy of both scores. Results: Among patients the five KS variables were distributed as follow: 15% of stomach/pancreas cancer (2points), 33% with lung/gynecologic cancer (1point), 24% with platelet count of ≥350x10^9/L, 7.9% hemoglobin 11x10^9/L (1point each variable) and only 1.3% with BMI ≥ 35 (1point). 15 TEs occurred in the 378 pts, below the TEs distribution according to KS and PrS (see table). The area under the ROC curve was larger with PrS in comparison with KS (0.70 and 0.65 respectively). Conclusions: BMI ≥ 35 seems not to be a predictable factor for TEs in European cancer patients and the use of a chemotherapy variable could be more useful to identify patient at high risk of TE. A formal study is needed to evaluate which score could have a higher predictability to identify high risk patients for TEs. [Table: see text]