Risk factors for thromboembolic events in testicular cancer patients receiving chemotherapy

e16109 Background: Cancer patients are at increased risk for thromboembolic events (TTEs), and those receiving chemotherapy are at even greater risk. Clinical experience and the literature have suggested that men receiving cisplatin-based chemotherapy for metastatic germ cell tumors are at particularly high risk. As TTEs can be fatal and treatment is curative, the stakes are high. Despite this, prophylactic anticoagulation (PA) is not routinely used. Methods: All men treated with cisplatin-based chemotherapy for metastatic germ cell cancer at the London Regional Cancer Program from January 1978 to December 2007 were identified from electronic databases. Data including type and timing of TTEs were extracted by retrospective chart review. Multivariable analyses were used to identify predictors of TTEs. Results: 196 eligible patients were identified with median age 31 years (range, 15–75). No patients received PA. Thirty-two TTEs were identified in 29 patients for an overall incidence of 14.8% (95% CI, 9.8–19.8%). The majority of events were deep venous thromboses, and five patients died due to TTE or its complications. Sixteen of the patients with TTE (55.2%) were diagnosed while on treatment (defined as TTE within 6 months of chemotherapy initiation); 8 (27.6%) had their TTE prior to, and 5 (17.2%) after this time period. Age greater than 30 years (OR = 3.02; 95% CI, 1.10–8.33; p = 0.033) and elevated LDH (OR = 1.93; 95% CI, 1.07–3.48; p = 0.029) were independently associated with an increased risk of TTE. If both adverse risk factors were present, the risk of TTE on treatment was 21.7% (95% CI, 9.8–33.7%). If neither were present, the negative predictive value was 97% (95% CI, 92–100%). Conclusions: The overall TTE incidence rate of 14.8% is consistent with prior reports (8.4–19%). The risk of TTE appears greatest during chemotherapy and shortly thereafter, and nearly one in 10 patients in this group had a TTE. These data support the concept of PA for selected patients starting chemotherapy for metastatic germ cell cancer. However, the efficacy of PA and risk of hemorrhage in this group is unknown. In this cohort, patients under 30 with normal LDH were at very low risk for TTE. Confirmation of these findings to help guide the study and optimal use of PA should be pursued. No significant financial relationships to disclose.