Development and validation of a predictive model for chemotherapy-associated thrombosis.
Risk of venous thromboembolism (VTE) is elevated in cancer, but individual risk factors cannot identify a sufficiently high-risk group of outpatients for thromboprophylaxis. We developed a simple model for predicting chemotherapy-associated VTE using baseline clinical and laboratory variables. The association of VTE with multiple variables was characterized in a derivation cohort of 2701 cancer outpatients from a prospective observational study. A risk model was derived and validated in an independent cohort of 1365 patients from the same study. Five predictive variables were identified in a multivariate model: site of cancer (2 points for very high-risk site, 1 point for high-risk site), platelet count of 350 x 10(9)/L or more, hemoglobin less than 100 g/L (10 g/dL) and/or use of erythropoiesis-stimulating agents, leukocyte count more than 11 x 10(9)/L, and body mass index of 35 kg/m(2) or more (1 point each). Rates of VTE in the derivation and validation cohorts, respectively, were 0.8% and 0.3% in low-risk (score = 0), 1.8% and 2% in intermediate-risk (score = 1-2), and 7.1% and 6.7% in high-risk (score >/= 3) category over a median of 2.5 months (C-statistic = 0.7 for both cohorts). This model can identify patients with a nearly 7% short-term risk of symptomatic VTE and may be used to select cancer outpatients for studies of thromboprophylaxis.
Khorana
Alok A
AA
James P. Wilmot Cancer Center and the Department of Medicine, University of Rochester, NY, USA. alok_khorana@urmc.rochester.edu
Kuderer
Nicole M
NM
Culakova
Eva
E
Lyman
Gary H
GH
Francis
Charles W
CW
D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects*; D015331:Cohort Studies; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009369:Neoplasms / Q000150:complications; D011237:Predictive Value of Tests; D018570:Risk Assessment; D013927:Thrombosis / Q000139:chemically induced*
D000970:Antineoplastic Agents