The significant interaction between treatment group and ER status indicated that the effect of NCT vs NCAT differed by ER status; for patients with ER negative tumours, NCT was significantly associated with a reduced risk of an event relative to NCAT (HR: 0.25; 95% CI, 0.1–0.62; p = 0.003), which was not observed for those with ER positive tumours (HR: 1.07; 95% CI, 0.46–2.52; p = 0.869) (Figure 4B). Here, ESR1 is linked to neoplasm.