Causes of Underarm Lump

We can describe underarm lump as a localized bump that may or may not be accompanied by pain and irritation. It is usually triggered by factors like allergic reactions or minor skin infections. When the lump is formed under the skin, it is due to swelling of the lymph nodes present in the underarm.

These oval-shaped glands basically act as filters that capture the malignant cells of the body and infection causing organisms. As the lymph nodes trap unwanted foreign particles, their size become bigger and can be felt as lumps in the armpit.

Although it is difficult to tell the exact cause of the lump simply by looking at it, you should be able to inform the doctor about the exact nature of the lump: whether it is painful, hard, soft, movable, increasing in size, etc.

There are several types of virus, bacteria, and fungus that can attack the skin surface of the underarm region and cause infection. As a result, boils and cysts break out on the skin. A bacterial or fungal skin infection occurs mainly due to lack of personal hygiene.

Sweat and dirt accumulated here creates a perfect breeding ground for these pathogens that trigger the infections. Chickenpox and shingles caused by viral attacks lead to formation of small, itchy blister like eruptions in the armpit and other parts of the body.

Men often get skin bumps in the form of boils after shaving their underarms. It mostly happens among adolescents who are inexperienced in shaving. Sometimes, painful armpit lump can be an allergic skin reaction towards certain ingredients of antiperspirants.

Large internal abscesses could be found in the armpit, which are not visible on the skin surface but can be felt as painful bump. Medicines that are used as vaccinations against diseases like typhoid, smallpox, measles, mumps, etc., can cause swelling in the lymph nodes.

Certain forms of cancer, like leukemia, are responsible for enlargement of underarm lymph glands. Women should not neglect any lump in the underarm region as it could be a warning sign of breast cancer. However, sometimes, normal breast tissues may get extended to that area and can be felt as painless armpit lumps which are absolutely harmless. Similarly, fatty growths and benign cysts in the armpit have no adverse effect on the health.

As mentioned above, the nature and type of the lump, its accompanying symptoms, etc., can help in diagnosing the underlying causes to a great extent. If none of these help, the doctor will ask the person to undergo an X-ray or CT scan. 

If an abscess or a cyst does not disappear within a week, or is extremely painful, then a doctor has to be consulted in order to remove it surgically. Symptoms of viral infections like shingles and chickenpox subside on their own as time passes by. An allergic reaction has to be prevented by avoiding the specific allergens.

The diagnosis of swollen lymph nodes involves physical examination, understanding the symptoms, and if required, some laboratory tests like lymph node biopsy are conducted. Any benign cyst or breast tissue do not require any form of treatment. In case, the lump is malignant, the treatment depends on the type of the cancer that has been diagnosed.

If a boil or cyst has formed in the underarm, then a good personal hygiene is a must. Usually, it does not require any other medicinal treatment.

• Wash the area a number of times throughout the day in order to keep the skin free from germs.
• Wear clean clothes made of natural fibers as too much of sweating can promote bacterial growth.

• Do not touch or squeeze the boils unnecessarily.
• Warm compression often helps in easing off the pain associated with such lumps.
• Within a week or so, the boil would burst. Let the pus drain out of the boil and then clean up the area immediately.

As you can see, some of the causes of underarm lumps are really serious and need immediate diagnosis and treatment. While conducting breast self-examination, women should always check their armpits too. If you discover even a small lump in the underarm, then you should not neglect the issue and consult your doctor to confirm its actual cause.

This story is intended only to provide information. It is not to be substituted for a doctor's advice and treatment.