Time dependence of biomarkers: non-proportional effects of immunohistochemical panels predicting relapse risk in early breast cancer.

ABSTRACT:

Background

We investigated the impact of follow-up duration to determine whether two immunohistochemical prognostic panels, IHC4 and Mammostrat, provide information on the risk of early or late distant recurrence using the Edinburgh Breast Conservation Series and the Tamoxifen vs Exemestane Adjuvant Multinational (TEAM) trial.

Methods

The multivariable fractional polynomial time (MFPT) algorithm was used to determine which variables had possible non-proportional effects. The performance of the scores was assessed at various lengths of follow-up and Cox regression modelling was performed over the intervals of 0-5 years and >5 years.

Results

We observed a strong time dependence of both the IHC4 and Mammostrat scores, with their effects decreasing over time. In the first

SUBMITTER: Stephen J 

PROVIDER: S-EPMC4264442 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature