Breast nodule grade 3 indicates a high likelihood of a benign nodule with a malignancy rate of <2%; blood flow signal is a sign of malignancy and can also be seen in benign lesions that are not serious overall. Breast BI-RADS (Breast Imaging Reporting and Data System) is an assessment of the risk of malignancy of breast nodules based on imaging such as breast ultrasound or molybdenum target, which can be categorized into 0 to 6. Grade 3 suggests a high likelihood of the nodule being benign, with a <2% likelihood of being a malignant nodule. Grade 3 breast nodules have a <2% likelihood of being malignant tumors such as breast cancer or sarcoma, and a >98% likelihood of being benign lesions such as acute mastitis, breast cysts, and fibromas. Malignant lesions may appear as blood-rich masses, so the presence of a blood flow signal suggests that a malignant lesion may be present. However, some malignant lesions may not have a high blood supply, while benign lesions such as papillomas and inflammatory lesions may also have a high blood supply, and the presence or absence of a blood flow signal is also related to the sensitivity and resolution of the examination instrumentation for blood flow. The presence of blood flow signal is not a specific manifestation of malignant lesions. Patients are advised to consult their specialists for a timely report and, if necessary, undergo another imaging examination such as ultrasound, molybdenum target, nuclear magnetic resonance imaging, or even a puncture biopsy.