With the development of society and the improvement of civilization, the prevalence of breast cancer is on an increasing trend. however, along with the advancement of technology, the understanding of breast cancer, treatment methods, drugs and efficacy have also been greatly improved. The cure rate of early stage breast cancer is much higher than late stage, and if detected early and treated timely and comprehensively, the survival rate can be almost unaffected! So, how to detect breast cancer early? Actually, this question is very simple! You can do it if you pay attention and respond scientifically. After all, breast is a superficial organ of the human body, and it is easier to detect the early signs of malignancy than other cancers, and breast cancer usually has a longer course, so it is possible to detect, diagnose and treat breast cancer at an early stage, thus achieving excellent results. Firstly, we should know what is early stage breast cancer? Afterwards, we should understand what methods can be used to detect breast cancer early. Early stage breast cancer is defined as a malignant tumor with a lesion less than 2 cm and no metastasis. Usually, it takes more than a year for a 1cm mass to grow, however, the earliest detectable lesions of a few millimeters can usually be detected by a test. Then, let’s learn how to detect early breast cancer lesions scientifically. 1. Self-examination of breast: Self-examination of breast is mainly visual examination and palpation of breast. (1) Visual examination of the breast should be done carefully to observe: ① The size and shape of both breasts, whether they are symmetrical, and whether there are any lumps or varicose veins protruding. (2) Whether the nipple is sunken or abnormally elevated. An abnormally elevated nipple caused by a breast lump is often a sign of a benign tumor; if it is accompanied by a sunken nipple, it is likely to be malignant. In addition, observe whether the nipple has flaking, erosion and eczema-like changes. (3) Changes of breast skin, whether there is redness, edema, depression, etc. (2) Breast palpation: It is generally easier to examine when lying down and compare with sitting. When lying down, shoulders slightly elevated, check the outer half of the hand should be raised over the head, so that the breast tissue flat in the chest wall, check the inner half of the hand can be placed at the side of the body, with the palm surface of the fingers flat and gentle palpation, can not use the hand to grasp and pinch, so as not to mistake normal breast tissue for lumps. The examination should be performed sequentially on each quadrant of the breast and the caudal part of the breast that protrudes into the axilla. The nipple should then be examined for abnormalities and fluid discharge. The examination should be done gently to prevent the spread of cancer cells due to squeezing. Finally, check whether there are enlarged lymph nodes in the axilla, subclavian and supraclavicular areas. In the process of self-examination, the following early symptoms need special attention: ① Breast lumps, especially those with hard texture, fast growth and poor mobility. ② Skin changes. When breast cancer invades the skin, it will cause abnormalities in the appearance, color and temperature of the skin. For example, the skin may become orange peel-like, darker and redder in color, accompanied by edema, thickening, and increase in surface temperature, and other inflammatory manifestations. ③ Nipple changes, we should pay attention to whether the nipple is sunken, elevated, and whether both nipples are at the same level and other abnormal performance. Breast cancer overflow is mostly seen in the single milk duct opening of unilateral breast. The nature of the overflow can be watery, blood-like or plasma blood-like. Breast cancer with nipple discharge as the only symptom is rare and is usually accompanied by breast lumps. ⑤ Superficial lymph nodes such as axillary lymph nodes or lymph nodes above and below the clavicle are enlarged. In case of the above cases, it is recommended to go to the hospital for systematic examination. (3) The best time for breast self-examination: For women with normal menstruation, the best time to have a breast examination is on the 7th to 10th day after menstruation because, at this time, estrogen has minimal effect on the breast and the breast is in a relatively static state, making it easy to detect lesions. If a lump appears during breastfeeding, if it is clinically suspected to be a tumor, it should be further examined after weaning. 2. Auxiliary examination methods: Clinical examination still has certain errors, even if physicians with rich clinical experience have a correct rate of about 70% to 80% for the examination of primary foci. Clinical examination of axillary lymph nodes has about 30% false negatives and 30-40% false positives, so other auxiliary diagnostic methods are needed to improve the correct rate of diagnosis. Commonly used auxiliary diagnostic methods are: (1) B-type ultrasound examination: it can show the structure of each layer of the breast, the shape and texture of the mass and its blood supply. Malignant tumors have irregular morphology and uneven echogenicity, while benign tumors often show uniform parenchymal changes. The correct rate of applying ultrasound to diagnose malignant tumor of breast is 87%. Ultrasound examination is better than X-ray in determining whether the tumor is substantial or cystic, but it is less capable of identifying tumors less than 1 cm in diameter. (2) Mammography: There are two types of mammography and dry plate radiography, both of which are suitable for observing the structure of soft tissue. The image of malignant tumor is irregular, lobulated and burr-like shadows, and its density is higher than that of the general gland. 30% of malignant lesions show piles of small sand-like calcified dots, in addition to thickening of ductal shadows, thickening of vascular shadows and thickening of skin. However, mammography is not recommended for women under 35 years of age. (3) Breast MRI: It has a high resolution of soft tissues and is more sensitive than mammography. It can observe the lesion in three dimensions and can provide not only the morphological characteristics of the lesion, but also the hemodynamic situation of the lesion with dynamic enhancement. Therefore, the use of MRI can provide more information for lesions that cannot be diagnosed by X-ray and ultrasound. Moreover, since MRI can detect smaller primary foci, it is more significant for the detection of occult breast cancer and is also often used for screening of high-risk groups. (4) Ductoscopy: mainly for patients with nipple overflow but no lump is found, it can be done under direct vision condition, and for patients with intraductal lesions, it can clearly diagnose and determine the site and scope of surgery. At the same time, cell samples can be obtained under the ductoscope for cytological examination or for the removal of some smaller benign masses using instruments. (5) Cytologic examination: cytologic smear can be performed to check for the presence of cancer cells in the presence of nipple discharge. If there is nipple erosion or eczema-like changes, cytological examination can be performed on the print. However, there is a certain possibility of false negatives or false positives. (6) Coarse needle aspiration or excisional biopsy: pathological examination of the lesion is the most reliable method to confirm the diagnosis and cannot be replaced by other examination methods. If it has been confirmed as malignant tumor (including breast cancer, sarcoma, lobular tumor, etc.), corresponding radical surgery should be performed in time to prevent the possible dissemination caused by biopsy surgery.