There is a hard lump in the armpit, the most common is the lymph node swelling in the armpit, commonly caused by inflammation, there are also some patients are due to trauma, induced by local lymph node reactive hyperplasia, such as exercise or muscle strain after exertion, also prone to this situation, you can choose the method of hot compress, can make the local lymph node swelling gradually subside. For inflammatory infections, anti-infection treatment should be applied, and broad-spectrum penicillin sodium should be administered intravenously, so that the patient’s condition can gradually improve. The most effective treatment is surgery, which is usually performed under local anesthesia. The lesion should be completely peeled off and excised to avoid recurrence after surgery, and the medication should be changed regularly after surgery.