A method for predicting the likelihood of a breast cancer patient's 5-year survival or the likelihood of recurrence of a breast cancer over a 5-year period in a breast cancer patient or the likelihood of a breast cancer patient's distant metastasis free survival (DMFS) over a 5-year period, said method comprising the steps: - measuring, in a tumor sample of said breast cancer patient, the mRNA expression levels of 5, 6, 7, 8 or all genes of a set of genes, said set of genes consisting of BIRC5, CCNB2, CDC6, MMP13, NEK2, RRM2, TOP2A, CENPE, and, optionally, MKI67 - comparing the measured mRNA expression levels from said tumor sample of said breast cancer patient with mRNA expression levels of the same genes in a non-tumor sample of a healthy individual or with mRNA expression levels of the same genes in a healthy, non-tumor sample of the same breast cancer patient, and either - determining, based on such comparison, whether there is an overexpression of the respective genes in said tumor sample of said breast cancer patient, wherein an overexpression of the mRNAs of each gene in said tumor sample of said patient in comparison to the mRNA expression levels of the same genes of said healthy individual or in said healthy, non-tumor sample of the same breast cancer patient is indicative of a likelihood of 5-year survival of <70% and/or of a likelihood of recurrence of said breast cancer over 5-year period of >30% or of a likelihood of DMFS over a 5-year period of <70%, or - determining, based on such comparison, whether there is a low overexpression, an intermediate overexpression or a high overexpression of the respective genes in said tumor sample of said breast cancer patient, wherein a low overexpression of the mRNAs of each gene in said tumor sample of said patient in comparison to the mRNA expression levels of the same genes of said healthy individual or in said healthy, non-tumor sample of the same breast cancer patient is indicative of a likelihood of 5-year survival of <95% and/or of a likelihood of recurrence of said breast cancer over 5-year period of >5% or of a likelihood of DMFS over a 5-year period of <95%, and wherein an intermediate overexpression of the mRNAs of each gene in said tumor sample of said patient in comparison to the mRNA expression levels of the same genes of said healthy individual or in said healthy, non-tumor sample of the same breast cancer patient is indicative of a likelihood of 5-year survival of <85% and/or of a likelihood of recurrence of said breast cancer over 5-year period of >15% or of a likelihood of DMFS over a 5-year period of <85%, and wherein a high overexpression of the mRNAs of each gene in said tumor sample of said patient in comparison to the mRNA expression levels of the same genes of said healthy individual or in said healthy, non-tumor sample of the same breast cancer patient is indicative of a likelihood of 5-year survival of <70% and/or of a likelihood of recurrence of said breast cancer over 5-year period of >30% or of a likelihood of DMFS over a 5-year period of <70%. - measuring, in a tumor sample of said breast cancer patient, the mRNA expression levels of 5, 6, 7, 8 or all genes of a set of genes, said set of genes consisting of BIRC5, CCNB2, CDC6, MMP13, NEK2, RRM2, TOP2A, CENPE, and, optionally, MKI67 - comparing the measured mRNA expression levels from said tumor sample of said breast cancer patient with mRNA expression levels of the same genes in a non-tumor sample of a healthy individual or with mRNA expression levels of the same genes in a healthy, non-tumor sample of the same breast cancer patient, and either - determining, based on such comparison, whether there is an overexpression of the respective genes in said tumor sample of said breast cancer patient, wherein an overexpression of the mRNAs of each gene in said tumor sample of said patient in comparison to the mRNA expression levels of the same genes of said healthy individual or in said healthy, non-tumor sample of the same breast cancer patient is indicative of a likelihood of 5-year survival of <70% and/or of a likelihood of recurrence of said breast cancer over 5-year period of >30% or of a likelihood of DMFS over a 5-year period of <70%, or - determining, based on such comparison, whether there is a low overexpression, an intermediate overexpression or a high overexpression of the respective genes in said tumor sample of said breast cancer patient,