I. Breast cancer, the most common malignant tumor in women. With early detection, early diagnosis and timely standardized treatment, breast cancer can be cured or have a better prognosis (longer survival time). If the diagnosis and treatment are missed or delayed, the prognosis or outcome is poor. How to detect and diagnose breast cancer at an early stage? 1. Palpable lump, dimple sign, orange peel sign, etc. – often it is already invasive cancer or middle to late stage breast cancer! Self-examination or doctor’s physical examination – far from enough! 2.Imaging examinations to find out impalpable lesions – can detect breast cancer at an early stage (1) Mammography, ultrasound and MRI can help to detect breast cancer at an early stage. (2) In Europe and America, mammography screening for breast cancer has been applied for many years and is the most widely used. Nowadays, it is being used more and more in large and medium-sized cities in China, and the effect is remarkable! (Early detection of breast cancer and reduction of breast cancer mortality) What is BI-RADS? BI-RADS (Breast imaging reporting and data system) was proposed and recommended by the American College of Radiology in 1992 as the “Breast Imaging Reporting and Data System”. In 2003, it was expanded to include ultrasound and MRI of the breast. The goal is to standardize the reporting of all normal and abnormal imaging of the breast as a whole organ, using uniform terminology, standard diagnostic categories and examination procedures. (a) Assessment is incomplete Grade 0: requires other imaging examinations for further evaluation or comparison with the anterior film. It is often used in census situations, but rarely after complete imaging and comparison with the anterior film. Other imaging methods recommended include localized compression photography, magnification, special projection posture photography, and ultrasound. (ii) Assessment is complete Grade 1: Negative. No abnormal findings. Grade 2: Benign findings. These include calcified fibroadenoma , multiple secretory calcifications, fat-containing lesions (lipid cysts, lipomas, ductal cysts and mixed density mismatched tumors) , intramammary lymph nodes, vascular calcifications, implants, structural distortions with a history of surgery, etc. Grade 3: Probably benign findings, short-term follow-up recommended. There is a high probability of benign findings and the expectation is that the lesion will stabilize or shrink over a short period of time (less than 1 year, usually 6 months) to confirm the determination. Grade 4: suspicious abnormality, biopsy should be considered. This level includes a large group of lesions that require clinical intervention, which do not have characteristic morphological changes of breast cancer, but have the possibility of malignancy, with an overall malignancy rate of about 30%. Grade 5: Highly suspicious of malignancy and clinically indicated (almost certain malignancy). This group of lesions has a high probability of malignancy. The probability of detecting malignancy is greater than or equal to 95%. High-density masses with irregular awning margins, segmental and linear distribution of small linear and branching calcifications, and irregular awning margins with polymorphic calcifications should be included in this class. Grade 6: Biopsy-confirmed malignancy, and appropriate measures should be taken. This grade is used for imaging evaluation of biopsy-proven malignancy that has not yet been treated. It is primarily used to evaluate imaging changes after prior biopsy or to monitor imaging changes from neoadjuvant chemotherapy prior to surgery. The standardization and accuracy of breast imaging and reporting is quite important. Accurate reporting is no longer an ancillary test, but rather the primary diagnostic basis and a key guide to the diagnosis, treatment and review of the disease.