ESR1 and metastatic malignant neoplasm in the lymph nodes: Most research suggests that rear echo attenuation is positively correlated with ER, a mass diameter > 2 cm is positively correlated with HER-2 and Ki-67, and a high CDFI score and lymph node metastasis are negatively correlated with ER and positively correlated with HER-2 [6, 7], findings that are consistent with most of the results in this study.