The invention relates to a method of predicting an outcome of a
breast cancer subject, comprising determining or receiving the result of a determination of a
gene expression profile comprising the expression levels of four or more genes selected from a first, a second and / or a third
gene expression profile, wherein the first
gene expression profile comprising one or more
immune defense response genes selected from the group consisting of: AIM2, APOBEC3A, CIAO1, DDX58, DHX9, IFI16, IFIH1, IFIT1, IFIT3, LRRFIP1, MYD88, OAS1, TLR8, and ZBP1, and / or the second
gene expression profile comprising one or more T-
Cell receptor signalling genes selected from the group consisting of: CD2, CD247, CD28, CD3E, CD3G, CD4, CSK, EZR, FYN, LAT, LCK, PAG1, PDE4D, PRKACA, PRKACB, PTPRC, and ZAP70, and / or the third
gene expression profile comprising one or more PDE4D7 correlated genes selected from the group consisting of: ABCC5, CUX2, KIAA1549, PDE4D, RAP1GAP2, SLC39A11, TDRD1, and VWA2, said
gene expression profile being determined in a biological sample obtained from the subject, determining the prediction of the outcome based on the gene expression profile comprising the expression levels of the four or more genes, wherein said prediction is a favourable risk or a non-favourable risk of breast-
cancer related death, loco-regional recurrence and / or distant recurrence.