title: Validation study of the prognostic value of cyclin-dependent kinase (CDK)-based risk in Caucasian breast cancer patients.
abstract: In a Japanese study, cyclin-dependent kinase (CDK) based risk determined by CDK 1 and 2 activities was associated with risk of distance recurrence in early breast cancer patients. The aim of our study was to validate this risk categorization in European early breast cancer patients. We retrospectively analyzed frozen breast cancer specimens of 352 Dutch patients with histologically confirmed primary invasive early breast cancer. CDK-based risk was determined in tumour tissues by calculating a risk score (RS) according to kinases activity and protein mass concentration assay without the knowledge of outcome. Determination of CDK-based risk was feasible in 184 out of 352 (52%) tumours. Median follow-up of these patients was 15 years. In patients not receiving systemic treatment, the proportions of risk categories were 44% low, 16% intermediate, and 40% high CDK-based risk. These groups remained significant after univariate and multivariate Cox-regression analysis. Factors associated with a shorter distant recurrence-free period were positive lymph nodes, mastectomy with radiotherapy, and high CDK-based risk. There was no significant correlation with overall survival (OS). CDK-based risk is a prognostic marker of distance recurrence of patients with early breast cancer. More validation would be warranted to use of CDK-based risk into clinical practice.
authors.affiliation: Department of Surgery, Leiden University Medical Centre, P.O. Box 9600, Leiden 2300 RC, the Netherlands.
authors.forename: J G H
authors.initials: JG
authors.lastname: van Nes
authors.forename: V T H B M
authors.initials: VT
authors.lastname: Smit
authors.forename: H
authors.initials: H
authors.lastname: Putter
authors.forename: P J
authors.initials: PJ
authors.lastname: Kuppen
authors.forename: S J
authors.initials: SJ
authors.lastname: Kim
authors.forename: M
authors.initials: M
authors.lastname: Daito
authors.forename: J
authors.initials: J
authors.lastname: Ding
authors.forename: M
authors.initials: M
authors.lastname: Shibayama
authors.forename: S
authors.initials: S
authors.lastname: Numada
authors.forename: K
authors.initials: K
authors.lastname: Gohda
authors.forename: T
authors.initials: T
authors.lastname: Matsushima
authors.forename: H
authors.initials: H
authors.lastname: Ishihara
authors.forename: S
authors.initials: S
authors.lastname: Noguchi
authors.forename: C J H
authors.initials: CJ
authors.lastname: van de Velde
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000201:enzymology* / Q000473:pathology; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D012307:Risk Factors; D016019:Survival Analysis; D044465:White People
chemical_list: D018844:Cyclin-Dependent Kinases