Where are the lymph nodes located in your armpit

Q: When should I worry about armpit lymph nodes?

See your doctor if youre concerned or if your swollen lymph nodes: Have appeared for no apparent reason. Continue to enlarge or have been present for two to four weeks. Feel hard or rubbery, or dont move when you push on them.

The axillary lymph nodes or armpit lymph nodes are lymph nodes in the human armpit. Between 20 and 49 in number, they drain lymph vessels from the lateral quadrants of the breast, the superficial lymph vessels from thin walls of the chest and the abdomen above the level of the navel, and the vessels from the upper limb. They are divided in several groups according to their location in the armpit. These lymph nodes are clinically significant in breast cancer, and metastases from the breast to the axillary lymph nodes are considered in the staging of the disease.[1]

Table of Contents Show

Structure[edit]
Breast cancer[edit]
What does a swollen lymph node in armpit feel like?
How do you check armpit lymph nodes?
What does a cancerous lymph node in armpit feel like?
When should I worry about armpit lymph nodes?

Structure[edit]

The axillary lymph nodes are arranged in six groups:

Anterior (pectoral) group: Lying along the lower border of the pectoralis minor behind the pectoralis major, these nodes receive lymph vessels from the lateral quadrants of the breast and superficial vessels from the anterolateral abdominal wall above the level of the umbilicus.
Posterior (subscapular) group: Lying in front of the subscapularis muscle, these nodes receive superficial lymph vessels from the back, down as far as the level of the iliac crests.
Lateral group: Lying along the medial side of the axillary vein, these nodes receive most of the lymph vessels of the upper limb (except those superficial vessels draining the lateral side—see infraclavicular nodes, below).
Central group: Lying in the center of the axilla in the axillary fat, these nodes receive lymph from the above three groups.
Infraclavicular (deltopectoral) group: These nodes are not strictly axillary nodes because they are located outside the axilla. They lie in the groove between the deltoid and pectoralis major muscles and receive superficial lymph vessels from the lateral side of the hand, forearm, and arm.
Apical group: Lying at the apex of the axilla at the lateral border of the 1st rib, these nodes receive the efferent lymph vessels from all the other axillary nodes.

The apical nodes drain into the subclavian lymph trunk. On the left side, this trunk drains into the thoracic duct; on the right side, it drains into the right lymphatic duct. Alternatively, the lymph trunks may drain directly into one of the large veins at the root of the neck.[2]

Breast cancer[edit]

Image illustrating sentinel lymph nodes. The axillary lymph nodes drain 75% of the lymph from the breasts and so may swell in cancer.

About 75% of lymph from the breasts drains into the axillary lymph nodes, making them important in the diagnosis and staging of breast cancer. A doctor will usually refer a patient to a surgeon to have an axillary lymph node dissection to see if the cancer cells have been trapped in the nodes. For clinical stages I and II breast cancer, axillary lymph node dissection should only be performed after first attempting sentinel node biopsy.[3]

If cancer cells are found in the nodes it increases the risk of metastatic breast cancer. Another method of determining breast cancer spread is to perform an endoscopic axillary sentinel node biopsy. This involves injecting a dye into the breast lump and seeing which node it first spread to (the sentinel node). This node is then removed and examined. If there is no cancer present, it is assumed the cancer has not spread to the other lymph nodes. This procedure is often less invasive and less damaging than the axillary lymph node dissection. The estimated risk of lymphedema following sentinel lymph node procedure is less than 3%.[citation needed] The approximate risk of lymphedema following axillary lymph node dissection is 10-15% and this can slightly increase with the addition of radiotherapy and chemotherapy to as much as 20-25% depending on the extent of dissection, extent of radiotherapy fields, and history of chemotherapy.[citation needed]

On CT scan or MRI, axillary lymphadenopathy can be defined as solid nodes measuring more than 1.5 cm without fatty hilum.[4] Lymph nodes may be normal up to 3 cm if consisting largely of fat.[4]

Axillary lymph nodes are included within the standard tangential fields in radiotherapy for breast cancer. In the case of comprehensive nodal irradiation, which includes axillary levels I, II, and III, as well as a supraclavicular lymph node field, there is a risk of damage to brachial plexus. The risk is estimated to be less than 5% as the brachial plexus radiation tolerance according to (Emami 1991) is 60 Gy in standard fractionation (2 Gy per fraction).[citation needed] A common prescribed dose for breast cancer with comprehensive nodal fields would be 50 Gy in 25 fractions with a boost planned to the lumpectomy cavity in the breast or scar on the chest wall if it is a mastectomy. If brachial plexopathy does occur, it is generally a late effect and may not manifest itself until 10 or 15 years later, and usually presents with slight painless muscular atrophy.

Malignancies in the gastrointestinal system like gastric cancer can metastasize to the left axillary lymph node which is called "Irish’s node".[5]

What does a swollen lymph node in armpit feel like?

Swollen lymph nodes will feel like soft, round bumps, and they may be the size of a pea or a grape. They might be tender to the touch, which indicates inflammation. In some cases, the lymph nodes will also look larger than usual.

How do you check armpit lymph nodes?

Remove top clothing down to the waist to get easy access to the armpits. Sit in a comfortable position. Check each armpit in turn. To check the left side lift your arm slightly then place the fingers of your right hand high into the armpit and then lower your arm.

What does a cancerous lymph node in armpit feel like?

A lump in the armpit tends to be more concerning if it is painless. A normal lymph node should have the shape of a lima bean and be firm while still having some give to it. A cancerous lymph node will often (but not always) become rock-hard and change shape to resemble a marble rather than a lima bean.

When should I worry about armpit lymph nodes?

See your doctor if you're concerned or if your swollen lymph nodes: Have appeared for no apparent reason. Continue to enlarge or have been present for two to four weeks. Feel hard or rubbery, or don't move when you push on them.