Currently, many women are aware that a painless, solitary, hard lump may be a breast cancer and are aware of regular checkups. In fact, in some breast cancers, or in the early stages of breast cancer, there is often no lump in the breast, but rather focal calcification on mammogram, glandular tangles, and so on. However, people tend to ignore the existence of these signs and do not realize that they may be a risk sign of breast cancer. Focal calcifications in the breast are mainly due to the presence of calcifications in the form of calcium salts in the breast tissue, which can be distributed in different tissues of the breast and are classified as benign calcifications, indeterminate calcifications and malignant calcifications. For example, calcifications produced by fibroadenoma and calcified images from necrosis of breast fat cells after injury are usually benign calcifications, which are coarser and have smooth edges. Calcifications in breast cancer may be caused by necrosis of the cancer cells of the breast or their secretions. Malignant calcifications are usually small, irregularly shaped, granular punctate calcifications or cast calcifications, and often appear clustered, linear or segmental in distribution. Benign calcifications can be followed up clinically at regular intervals and treated once changes are detected; surgical biopsy is necessary for calcifications that are highly suspected of being malignant. Because the mass cannot be palpated and there are no abnormal findings on ultrasound, preoperative placement of a fine needle at the lesion under mammography stereotactic localization is required, and complete excision of focal calcifications in the direction of the fine needle guide is performed during surgery. We have detected many cases of in situ breast cancer by this method, which can be cured by the corresponding surgery. In fact, breast calcification is not scary, what is scary is the disregard for mammography, the neglect of finding calcification and the disregard for doctors’ advice. In our medical practice, we have encountered such patients who delayed and delayed their disease, escalating in situ cancer to invasive cancer and losing the good chance of cure, which eventually left lifelong regret.