Breast cancer prognostication and screening kits and methods of using same

A genetic biomarker panel is provided for prognosing late onset ER+ breast cancer relapse, in a breast cancer survivor patient. Kits are also provided for measuring levels or the presence of an identified panel of genetic biomarkers. Methods are also provided for identifying a breast cancer survivor patient at a relatively high risk of suffering a breast cancer relapse within 8 years of diagnosis, and therefore suitable for treatment with an aggressive chemotherapeutic regimen. The method may also be used for identifying a breast cancer survivor patient not at high risk of suffering a breast cancer relapse within 8 years of diagnosis, and thus not suitable for treatment with an aggressive chemotherapeutic regimen. The genetic biomarker panel includes an oligonucleotide/nucleic acid sequence specific for the following genes: MKI67, SPAG5, ESPL1, PLK1, or a genetic panel for MKI67, SPAG5, ESPL1, PLK1 and PGR.