title: Factor v leiden mutation in patients with breast cancer with a central venous catheter: risk of deep vein thrombosis.
abstract: BACKGROUND
  The objective of this study was to analyze the influence of the prothrombotic factor V Leiden (FVL) and G20210A prothrombin mutations on the frequency of the first episode of catheter-related deep vein thrombosis (DVT) in a cohort of patients with locally advanced or metastatic breast cancer during continuous venous insult (infusion of 5-fluorouracil-based chemotherapy).
  
  
  METHODS
  Between January 1999 and February 2001, we retrospectively analyzed the incidence of first DVT in 300 consecutive patients with locally advanced or metastatic breast cancer treated at a single institution with a combination of chemotherapy administered continuously through a totally implanted access port. We identified 25 women (study group) with catheter-related DVT. For each of the 25 patients, we selected 2 women eligible for identical chemotherapy who had similar age, stage of disease, and prognostic features as a control group. The prothrombotic FVL and prothrombin mutation G20210A genotype analyses were performed in all patients. Analyses were performed on blinded samples, and all patients signed a specific informed consent form. A total of 25 cases (with thrombosis) and 50 frequency-matched controls were evaluated for FVL.
  
  
  RESULTS
  Five cases and 2 controls were found with the mutation in the FVL, for incidences of 20% (95% CI, 9%-39%) and 4% (95% CI, 1%-14%), respectively. Thus, the frequency of the mutation was significantly higher in the cases than in controls (P = 0.04), and a logistic regression analysis, adjusted by age, yielded an odds ratio of 6.1 (95% CI, 1.1%-34.3%; P = 0.04). Time from start of infusion chemotherapy to thrombosis was not significantly different between those with the mutation (median, 31 days) and without the mutation (median, 43 days; P = 0.6). Only 1 subject (in the case group) was found with the G20210A mutation in the prothrombin gene.
  
  
  CONCLUSIONS
  Factor V Leiden carriers with locally advanced or metastatic breast cancer are at high risk of catheter-related DVT during chemotherapy. Clinicians should be aware of this increased risk, and alternative cytotoxic treatments not requiring continuous infusions should be considered for these patients.
authors.affiliation: Division of Medical Oncology, Clinical Pharmacology and New Drugs Development Unit, European Institute of Oncology, Milan, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Curigliano
authors.forename: Mario
authors.initials: M
authors.lastname: Mandalà
authors.forename: Alberto
authors.initials: A
authors.lastname: Sbanotto
authors.forename: Marco
authors.initials: M
authors.lastname: Colleoni
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Ferretti
authors.forename: Paolo
authors.initials: P
authors.lastname: Bucciarelli
authors.forename: Giulia
authors.initials: G
authors.lastname: Peruzzotti
authors.forename: Filippo
authors.initials: F
authors.lastname: de Braud
authors.forename: Tommaso
authors.initials: T
authors.lastname: De Pas
authors.forename: Gianluca
authors.initials: G
authors.lastname: Spitaleri
authors.forename: E
authors.initials: E
authors.lastname: Pietri
authors.forename: Franco
authors.initials: F
authors.lastname: Orsi
authors.forename: Maria G
authors.initials: MG
authors.lastname: Banfi
authors.forename: Aron
authors.initials: A
authors.lastname: Goldhirsch