ESR1 and invasive breast carcinoma: The major findings of the present study were as follows: 1) VI shows a certain degree of correlation with the molecular subtype in invasive breast cancer; 2) ER negativity, higher tumor grade, and higher Ki-67 index (≥20%) were significantly associated with a higher VI value; (3) Tumor size, ER status, and Ki-67 index were shown to independently influence VI; (4) VI was of value in predicting the luminal A with high sensitivity and PPV and triple-negative type with high specificity and NPV.