An armpit lump can be caused by a variety of factors, including abnormal tissue growth, infections, skin irritations, and chronic diseases. The lump may feel soft or hard to the touch, depending on the underlying cause. Here are some possible causes of armpit lumps:
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Enlarged lymph nodes: This is the most common cause of armpit lumps. Lymph nodes can become swollen due to infections, such as colds, flu, or mononucleosis, or due to cancer.
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Cysts: These are fluid-filled sacs that can form in the armpit due to blocked hair follicles, infections, or other causes. Cysts may feel soft to the touch.
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Skin tags: Also known as acrochordons, skin tags can form in the armpit due to friction between skin folds. They may feel like a lump and can grow up to a few centimeters in size.
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Lipomas: These are benign fatty growths that can develop just beneath the skin. They are usually harmless but can be irritating or unsightly.
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Allergic reactions: An allergic reaction to deodorant, antiperspirant, soap, or other substances can cause a lump in the armpit. The lump may feel soft or hard, depending on the severity of the reaction.
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Injuries: Trauma to the armpit area, such as from a blow in contact sports or a car accident, can cause a lump to form.
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Vaccinations: Some vaccines can cause a lump in the armpit as a side effect. This is usually a sign that the vaccine is working and will go away on its own.
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Breast cancer: In rare cases, an armpit lump can be a sign of breast cancer that has spread to the lymph nodes. However, most armpit lumps are not cancerous.
To determine the cause of an armpit lump, a doctor may perform a physical examination and order additional tests, such as a biopsy, complete blood count, or imaging tests. Treatment recommendations will depend on the underlying cause of the lump. In some cases, no treatment may be necessary, and the lump may go away on its own[[5]](https://my...
