There are many reasons why the chest is so big and small, as follows: 1, congenital chest size is genetically determined normal physiological structure, does not affect the aesthetic, can not be dealt with. 2, lymph node swelling. If it affects your life, you can undergo surgical plastic surgery.2. Enlarged lymph nodes. Lymph nodes are stimulated to cause enlargement of one side of the breast, you can first control the inflammation with fluids, and then undergo surgery to remove the enlarged lymph nodes.3. Breast diseases. For example, breast hyperplasia and breast fibroids can lead to breast enlargement. Breast hyperplasia can be regulated by taking lactic acid, and then surgery can be performed to remove the hyperplasia; breast fibroids need to be surgically removed as soon as they are found. Mastitis patients with milk stagnation, breast swelling and enlargement, need to empty the milk, the use of drugs to reduce inflammation, if there is pus, need to be cut and drain pus. Breast cancer patients need early surgery and postoperative chemotherapy.