Analysis of breast cancer tissue samples. Forty-six breast cancer tissue samples originally analyzed for EGFR expression by a radio-ligand binding assay were reanalyzed in a bead-based ligand binding assay. A cut-off value of 10 fmol EGFR per mg protein, determined by radio-ligand binding assay, was used to divide the samples into group A () with EGFR values ≤10 fmol/mg and group B () with EGFR values >10 fmol/mg. Samples were measured in a random order, and a value of 2.6e-11 was calculated between the two groups.
