A method of determining a prognosis of a breast cancer patient comprising the following steps: a. contacting a lymph node metastasis sample obtained from the patient with a first molecular probe specific for GATA 3 conjugated to a detectable label, and a second molecular probe, conjugated to a detectable label, and specific for p53; b. determining an expression level of GATA3 and an expression level of p53; c. assigning to the patient a good prognosis if the patient sample is characterised by a GATA3 expression level greater than or equal to (≥) a GATA3 threshold, and/or a p53 expression level below (<) a p53 threshold, or assigning to the patient a poor prognosis if the patient sample is characterised by a p53 expression level ≥ the p53 threshold, and/or a GATA3 expression level < the GATA3 threshold; and wherein the biomarker expression level is determined at the level of the whole sample, or a portion of the sample comprising a plurality of cells, and wherein - the GATA3 threshold is 100 times ≥ a negative control expression level; and - the p53 is threshold is ≥ 8 times a negative control expression level; and wherein the negative control expression level is the biomarker expression level determined for a negative control sample; or wherein the biomarker expression level is determined at the level of a single cell for each of a plurality of individual cells present in the sample, wherein - the GATA3 threshold is ≥ 20% GATA3 high cells; and - the p53 threshold is ≥ 6% p53 high cells, and wherein a cell is classified as high for biomarker expression if the biomarker expression level of the cell is ≥ 10 times the biomarker expression level of a cell in a negative control sample. a. contacting a lymph node metastasis sample obtained from the patient with a first molecular probe specific for GATA 3 conjugated to a detectable label, and a second molecular probe, conjugated to a detectable label, and specific for p53; b. determining an expression level of GATA3 and an expression level of p53; c. assigning to the patient a good prognosis if the patient sample is characterised by a GATA3 expression level greater than or equal to (≥) a GATA3 threshold, and/or a p53 expression level below (<) a p53 threshold, or assigning to the patient a poor prognosis if the patient sample is characterised by a p53 expression level ≥ the p53 threshold, and/or a GATA3 expression level < the GATA3 threshold; and wherein the biomarker expression level is determined at the level of the whole sample, or a portion of the sample comprising a plurality of cells, and wherein - the GATA3 threshold is 100 times ≥ a negative control expression level; and - the p53 is threshold is ≥ 8 times a negative control expression level; and wherein the negative control expression level is the biomarker expression level determined for a negative control sample; or wherein the biomarker expression level is determined at the level of a single cell for each of a plurality of individual cells present in the sample, wherein - the GATA3 threshold is ≥ 20% GATA3 high cells; and - the p53 threshold is ≥ 6% p53 high cells, and wherein a cell is classified as high for biomarker expression if the biomarker expression level of the cell is ≥ 10 times the biomarker expression level of a cell in a negative control sample. assigning to the patient a poor prognosis if the patient sample is characterised by a p53 expression level ≥ the p53 threshold, and/or a GATA3 expression level < the GATA3 threshold; and wherein the biomarker expression level is determined at the level of the whole sample, or a portion of the sample comprising a plurality of cells, and wherein - the GATA3 threshold is 100 times ≥ a negative control expression level; and - the p53 is threshold is ≥ 8 times a negative control expression level; and wherein the negative control expression level is the biomarker expression level determined for a negative control sample; or - the GATA3 threshold is 100 times ≥ a negative control expression level; and - the p53 is threshold is ≥ 8 times a negative control expression level; wherein the biomarker expression level is determined at the level of a single cell for each of a plurality of individual cells present in the sample, wherein - the GATA3 threshold is ≥ 20% GATA3 high cells; and - the p53 threshold is ≥ 6% p53 high cells, and wherein a cell is classified as high for biomarker expression if the biomarker expression level of the cell is ≥ 10 times the biomarker expression level of a cell in a negative control sample. - the GATA3 threshold is ≥ 20% GATA3 high cells; and - the p53 threshold is ≥ 6% p53 high cells,