Fig. 3

Agreement in the 21-gene signature and experimental recurrence scores between paired breast cancer samples. Paired breast cancer samples were collected from women with invasive, ER-positive breast cancer (n = 25). The 21-gene signature was assessed through real-time PCR. a Forest plot showing concordance in gene expression between sample 1 and sample 2, for the genes which comprise the Oncotype DX 21-gene signature. To determine if gene expression varied significantly between paired samples, statistical significance was assessed using linear mixed-effect models adjusted for multiple comparisons. No data were statistically significant (p > 0.05). b Correlation in experimental recurrence scores between paired samples. Recurrence scores were calculated from reference-normalised gene expression as described in the “Methods” section. Sample 1 corresponds to the first collected sample, presented against its corresponding later collected pair, sample 2. The dashed line represents perfect correlation, where deviation from the line reflects discordance between paired samples. Spearman’s correlations and p values are presented