The reason for this is that there are a lot of reasons for the axillary lymph node metastases, such as folliculitis, sebaceous cysts, lymphadenopathy, parametrium, lipoma, and breast cancer. 1, folliculitis: because of the relatively large number of hair in the armpit, sometimes there will be red papules and even small pustules secondary to bacterial infection, and pain and itching. The day-to-day attention should be paid to local cleanliness and dryness, to avoid excessive strain and tension, can be treated with topical antibiotics; 2, sebaceous cysts: due to sebaceous gland excretory duct obstruction, resulting in the expansion of the contents, and then the formation of cysts. The hardness and size of the tumor varies, and the squeezing will produce tofu-like secretions with rotten smell, and also with secondary infections, such as swelling, pain, fever, etc. It is recommended that the above symptoms can be surgically removed at the hospital; 3, lymphadenopathy: due to inflammation of the tissues or organs in the axillary lymph node reflux area, resulting in enlarged lymph nodes with pain, which may cause the patient to have a significant painful sensation; 4. Parametrium: Parametrium is the same as normal breast and will be painful and swollen during menstruation, or painful on contact, and the symptoms will gradually disappear after menstruation. There are sometimes small nipples on the surface of the parametrium, which is a relatively common physiological phenomenon; 5. Lipoma: It is a more common benign tumor that can appear in areas with fat. It is not easy to occur under normal circumstances, but when the resistance of the body decreases, it will make the tumor-causing factors of lipoma become active and lead to the appearance of lipoma. If the fatty tumor gradually increases, you can choose surgery to remove it; 6. Breast cancer axillary lymph node metastasis: If there are obvious lumps in the axilla, you should pay attention to them because breast cancer may also lead to unilateral lumps in the axilla and most of them are not painful, so it is easy to ignore them. There are many reasons for the lumps in the armpit. No matter what the cause of the lumps is, it is necessary to go to the general surgery department of the hospital for a complete examination to make a clear diagnosis.