Among those participants not using endocrine therapy, higher 27-HC levels were associated with a higher risk of recurrences (HRlog2 = 2.42 (1.11–5.28)); when further stratifying non-endocrine therapy users, the effect was only observed in hormone-receptor negative participants (all cause-death, HRlog2 = 3.09 (1.23–7.76); BC-specific death, HRlog2 = 3.96 (1.23–12.77); recurrences, HRlog2 = 3.50 (1.42–8.62)), and in low-estradiol participants (all-cause death, HRlog2 = 4.42 (1.28-15.24); BC-specific death, HRlog2 = 5.27 (1.19–23.25); recurrences, HRlog2 = 3.82 (1.25–11.64)). The gene discussed is NR4A1; the disease is breast cancer.