Development and validation of a risk assessment nomogram for venous thromboembolism associated with hospitalized postoperative Chinese breast cancer patients

Abstract Aim The purpose of this study was to develop and validate an individualized nomogram to predict venous thromboembolism (VTE) risk in hospitalized postoperative breast cancer patients. Design A single‐central retrospective and non‐interventional trial. Methods For model development, we used data from 4,755 breast cancer patients between 1 November 2016–30 June 2018 (3,310 patients in the development group and 1,445 in the validation group). Overall, 216 patients developed VTE (150 in development group and 66 in validation group). The model was validated by receiver operating characteristic curves and the calibration plot. The clinical utility of the model was determined through decision curve analysis. Results The individualized nomogram consisted of six clinical factors: age, body mass index, number of cardiovascular comorbidities, neoadjuvant chemotherapy, surgical treatment, hospital length of stay and two pre‐operative biomarkers of Homocysteine and D‐dimer. The model at the 3.9% optimal cut‐off had the area under the curve of 0.854 (95% CI, 0.824–0.884) and 0.805 (95% CI, 0.740–0.870) in the development and validation groups. A p = 0.570 of the calibration test showed that the model was well‐calibrated. The net benefit of the model was better between threshold probabilities of 5%–30% in decision curve analysis. Conclusion The nomogram of VTE risk assessment, is applicable to hospitalized postoperative breast cancer patients. However, multi‐central prospective studies are needed to improve and validate the model. Effectiveness and safety of thromboprophylaxis in high‐risk patients are needed to demonstrate in interventional trials. Impact This nomogram can be used in clinical to inform practice of physicians and nurses to predict the VTE probability and maybe direct personalized decision making for thromboprophylaxis in hospitalized postoperative breast cancer patients.