NICE advocates the utilisation of ODX testing in estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, node-negative early breast cancer only if patients 'have an intermediate-risk of distant recurrence using a validated tool such as PREDICT or the NPI and the information provided by the ODX testing will inform adjuvant chemotherapy treatment decisions. Here, ESR1 is linked to breast carcinoma.