title: Breast cancer-associated venous thromboembolism: A case-control study.
abstract: Breast cancer is frequently associated with venous thromboembolism (VTE). VTE may result in significant morbidity, a substantial economic burden and even leads to patients' death. Risk factor identification and management of VTE in breast cancer patients remains poorly studied. We evaluated breast cancer patients' baseline and treatment characteristics in predicting VTE occurrence as well as its prognosis. We conducted a case-control study of all breast cancer patients with a VTE diagnosed between January 2007 and December 2011 at the Instituto Nacional de Câncer (INCA) in Brazil. Two hundred and twenty five patients developed VTE and were compared with 225 controls, in the 5-year study period. The bulk of the thrombotic events were unilateral (94.2%) VTEs of the lower extremity (78.7%), largely proximally located (78%). VTE occurred more often within the first 3 years after the diagnosis of cancer (66.2%), being more common in the first 6 months (21.8%). Significant predictors of developing VTE were age 50 years and over (OR 1.85, 95% CI: 1.16-2.95), PS equal to or above 3 (OR 2.01, 95% CI: 1.24-3.26), and the presence of a CVC (OR 2.56, 95% CI: 1.42-4.62). This large retrospective analysis of VTE in breast cancer patients confirms that most events occur early in the treatment course. The incidence of VTE was associated with patients' age, PS, and the presence of CVC. Prospective studies are needed to evaluate outpatient thromboprophylaxis for selected groups of patients.
authors.affiliation: Department of Medical Oncology, Instituto Nacional de Câncer, Rua Visconde de Santa Isabel 274, Rio de Janeiro 20560-120, Brazil.
authors.forename: Danilo
authors.initials: D
authors.lastname: Rebouças
authors.affiliation: Department of Radiology, Instituto Nacional de Câncer, Rua Visconde de Santa Isabel 274, Rio de Janeiro 20560-120, Rio de Janeiro, Brazil.
authors.forename: Maria
authors.initials: M
authors.lastname: Costa
authors.affiliation: Department of Clinical Research, Instituto Nacional de Câncer, Rua Visconde de Santa Isabel 274, Rio de Janeiro 20560-120, Rio de Janeiro, Brazil.
authors.forename: Luiz
authors.initials: L
authors.lastname: Thuler
authors.affiliation: Department of Medical Oncology, Instituto Nacional de Câncer, Rua Visconde de Santa Isabel 274, Rio de Janeiro 20560-120, Brazil.
authors.forename: Alvaro
authors.initials: A
authors.lastname: Garces
authors.affiliation: Department of Medical Oncology, Instituto Nacional de Câncer, Rua Visconde de Santa Isabel 274, Rio de Janeiro 20560-120, Brazil.
authors.forename: Luciana
authors.initials: L
authors.lastname: Aquino
authors.affiliation: Department of Medical Oncology, Instituto Nacional de Câncer, Rua Visconde de Santa Isabel 274, Rio de Janeiro 20560-120, Brazil. Electronic address: jose_bines@yahoo.com.
authors.forename: José
authors.initials: J
authors.lastname: Bines
mesh_terms: D000367:Age Factors; D001943:Breast Neoplasms / Q000453:epidemiology*; D016022:Case-Control Studies; D062905:Central Venous Catheters; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000098:blood supply; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D015996:Survival Rate; D013997:Time Factors; D054556:Venous Thromboembolism / Q000000981:diagnostic imaging / Q000453:epidemiology*
keywords: Breast cancer; Case control; Deep venous thrombosis; Risk factors; Thromboembolic events; Thromboembolism