Lymph nodes

Lymph nodes are body organs (not glands) spread throughout your body. Their function is to filter out all the dead bacteria, viruses, and other dead tissue from the lymphatic fluid and eliminate it from the body. They are also the place where the white blood cells (lymphocytes) spend much of their time. When the immune system is activated they begin producing large numbers of lymphocytes which causes them to swell.

There are about 500-700 lymph nodes spread throughout the body. Click on the diagrams below for highly detailed pictures of where the lymph nodes are located. Below the pictures you will find information about the proper size that lymph nodes should be, their names, and a quick summary of how they feel and what it means.

Before you panic about why your lymph nodes are swollen please read the following articles about the causes of swollen lymph nodes.  

• Lymphadenopathy and Malignancy from the American Academy of Family Physicians
   
• Lymphadenopathy: Differential Diagnosis and Evaluation

Head neck nodes	Axillary nodes	Mediastinal (chest) nodes	Lung nodes
Arm nodes	Messenteric nodes front	Messenteric nodes back	Inguinal nodes female
Inguinal nodes male	Leg nodes front	Leg nodes back

Some of the common names of the lymph node locations you will encounter are :

• Cervical - Nodes in the neck
• Axillary - Nodes in the armpits
• Supraclavicular - Nodes along the collar bone
• Mediastinal - Nodes in the upper body behind the sternum and between the pleural sacs (lung sacs)
• Mesentery - Nodes in the lower body (abdomen) below the rib cage
• Inguinal - Nodes in the groin
• Femoral - Nodes in the upper inner thigh

Most normal lymph nodes are about 1cm in size (0.5 to 2.0cm) but that size varies depending on the location of the node, and what activity is going on. Infections, cancer and many other conditions can cause it to expand as the immune system reacts to the problem. Abnormal size is defined as: 

• Epitrochlear Lymphadenopathy >0.5 cm
• Inguinal Lymphadenopathy >1.5 cm
• Isolated lymphadenopathy in children >1.5 to 2.0 cm
• Other lymphadenopathy >1.0 cm

Note: Epitrochlear in layman's terms means near the elbow or funny bone

The following links will give you excellent detailed information about lymphadenopathy, and the many things that cause it besides cancer.

• Being tender does not differentiate between normal and cancerous.
• Rock hard nodes are more likely from some other type of metastatic cancer not lymphoma
• Firm but rubbery nodes could be lymphoma
• Soft nodes are most likely infection.
• Shotty nodes (multiple buckshot size) are likely viral in nature