Underarm Swelling Evaluation in Gomti Nagar, Lucknow

The armpit holds a group of lymph nodes, small bean-shaped glands that filter fluid draining from the arm, the breast and the upper chest. When they fight an infection or react to something nearby, they swell. This is the most common cause of underarm swelling, and it is usually a healthy response.

Common triggers are an infected hair follicle or boil, often after shaving or waxing. A cut, insect bite or skin infection in the hand, arm or breast can do it too. So can a recent vaccination in the same arm, or a viral illness such as a cold. These nodes are usually tender, soft and movable, and they shrink over a few weeks.

A lump in the armpit is not always a node. Extra breast tissue can sit in the armpit and swell with periods, pregnancy or breastfeeding. A lipoma, which is a soft fatty lump, or a cyst in the skin can also feel like a node. A scan can tell these apart.

Less often, nodes stay enlarged because of a longer-lasting infection such as tuberculosis, a disease of the lymph system or blood, or cancer that has spread from the breast or elsewhere. These are less common than the causes above, and tests are needed to tell them apart.

A lump should be examined when it has any of these features:

• It is hard, firm or fixed, and does not move under the skin.
• It does not hurt and keeps growing.
• It has not gone down within about two weeks, or it keeps coming back.
• There is a lump, nipple discharge or skin change in the breast on the same side.
• You have a fever that lasts, night sweats or unexplained weight loss.

Tender, soft nodes that appear with a cold or after a cut are far more often harmless. Even so, if you cannot tell which kind you have, it is reasonable to have it checked.

Assessment starts with your story and an examination. You are asked how long the swelling has been there, whether it hurts, and about infections, cuts, vaccinations, shaving, breast symptoms, fever and weight loss. Both underarms, the breasts and the neck are examined.

An underarm ultrasound is the usual first scan. It uses the same sound-wave method as the general ultrasound test and shows the size and shape of each node, the thickness of its outer layer and whether its pale fatty centre is still present. A healthy or reacting node usually stays oval with that fatty centre. Colour Doppler can add information about blood flow in the node.

A breast ultrasound is added when there is a breast symptom, and a mammogram when your age or findings call for it. The underarm nodes drain the breast, so a breast problem can show up first as a swollen node.

If a node looks abnormal, the next step may be a needle test of the node, as described on the breast FNAC and breast biopsy pages. If a node looks reactive, your doctor may simply advise a repeat scan after a few weeks. Your doctor may also ask for blood tests to look for infection and other causes.

Yes. After a vaccine, the nodes under the arm on the injected side can swell and feel tender for days or a few weeks. This is a normal immune response and usually settles without treatment.

The swelling can also show on scans, so tell the team the date and the arm of any recent vaccination when you book. If it is still there well after that, or you have other symptoms, see your doctor.