ESR1 and neoplasm: Several studies have confirmed that the Memorial Sloan Kettering Cancer Center nomogram based on nine clinicopathological variables, such as age, tumor size, tumor type, tumor location, lymphovascular invasion, multifocality, histological grade, ER status, and PR status, can be utilized to accurately and noninvasively assess the risk of ALN-SLNB metastasis in patients with breast cancer (15, 18).