Mammography primarily checks for any issues in a woman's breast, such as space-occupying lesions, which can be simply understood as a method specifically for screening breast cancer. Mammography is generally performed in the radiology department, where each breast is compressed using a flat panel, and then images are taken to look for any suspicious nodules. Generally speaking, it is adequate to perform this examination once a year. If one prefers not to undergo mammography, breast ultrasound can also be used to screen for breast cancer. If performed annually, it can effectively detect early cancerous changes or suspicious nodules, and if necessary, further treatment or assessment can be undertaken.