The armpit is also known as the armpit. When there are hard bumps in the flesh under the armpit that are painful to touch, it is generally considered that this condition may be due to conditions such as folliculitis, sebaceous cysts, paronychia, lipoma, and breast cancer. It is recommended that patients should go to the hospital for examination as soon as possible to identify the cause and treat the problem to avoid delaying the condition and causing serious consequences. Common causes and treatments 1. Folliculitis: When invading the axillary tissue, it can cause patients to have symptoms such as axillary meatballs, local pain and itching. Generally mild cases do not require special treatment, and serious cases may need to be treated with medication, which is easier to heal; 2. Sebaceous cysts: are caused by the blockage of sebaceous ducts in the axillary skin, resulting in the gradual accumulation of sebum to form sebaceous cysts. When accompanied by infection, there will be local symptoms such as redness, swelling, pus and pain, so it will cause a hard lump under the armpit that is painful to touch. The cysts are usually treated by surgical excision, and when accompanied by infection, active anti-infection treatment is required. If the cysts are completely removed by surgery, the prognosis is generally good; 3. Parammary glands: they often show symmetrical enlargement of the axillae bilaterally, and will be distended and painful during menstruation, and the symptoms will improve after menstruation, and the skin and fat internal glands can be felt when touched. If the gland is thicker and combined with hyperplasia, it will cause a hard and painful lump in the flesh under the armpit. When there is a gradual increase in size within a short period of time and the pain is aggravated, it can be treated by surgical excision to avoid malignancy, and the prognosis is generally better after surgical excision; 4. Lipoma: Because lipomas are often found in the axilla, neck, shoulder and other places, when the onset of the site for the axilla, there will be multiple lumps of different sizes or a single, resulting in a hard lump in the flesh under the armpit that hurts to feel. Most of them are benign tumors, which usually only need to be observed. If the tumor is large, it may cause pain, dysfunction and other symptoms, or affect the aesthetics, you can choose surgery to remove it, which has a better prognosis; 5. Breast cancer: breast cancer is metastatic, and when the malignant tumor metastasizes to the armpit, it will lead to painful hard bumps in the flesh under the armpit. When breast cancer has metastasized, local radiation therapy, intravenous chemotherapy, endocrine therapy and gene targeted therapy can be given. The general cure rate is low, but active treatment can improve the survival rate as well as the quality of life of patients. Precautions In daily life, pay attention not to rub and pinch the hard bumps under the armpit at will to reduce local stimulation, and also pay attention to change clothes regularly to keep clean and hygienic.