Mammogram 4a is not very likely to be cancerous. Mammography grading of the breast refers to the standardization of the severity of the breast, which is divided into seven grades, and the higher the grade value, the higher the risk of breast cancer. grade 4 belongs to the level of suspicion, which is further divided into grade a, grade b, and grade c. Among them, grade 4a is the suspicious malignant lesion of low suspicion, and although most of the results of its pathology report show that the lesion is benign, but before obtaining the report of the benign cytology report, regular re-examination and follow-up is required, which will last for half a year. Regular review and follow up needs to be done continuously for six months. If the diagnosis is benign, regular review is sufficient. If the result is malignant, or if the mass grows too fast, with abnormal pain or other uncomfortable symptoms, attention needs to be paid to it, and surgical resection and pathologic examination are required. Therefore, when the result of molybdenum target is 4a, one should pay attention to timely review and observe whether there is any possibility of cancer at any time.