Some authors suggest that some factors such as tumour grade might serve as a guide during decision-making for patients with whom the ODX-RS test can be avoided and just recommend endocrine therapy alone in those low-risk patients; also, they suggest recommending the adjuvant chemotherapy for ER-positive, HER2-negative, N0 high-risk patients without testing the ODX-RS such as those having large, high-grade, or progesterone receptor-negative tumours [26]. Here, ERBB2 is linked to neoplasm.