Q: I have developed small swellings in the side of my neck just in front of the jaw joint. I noticed them before, but they always went away. This time they have remained. Do you think that I have cancer?
-- B.Y., Hoffman Estates, Ill.
A: Given your description, including location and the pattern of appearance, my best guess is that the swelling is in your lymph nodes. Although they could be a sign of cancer, the chances are small. Let me explain.
Several barriers and responses work together to protect the body against infection and cancer. Physical barriers such as the skin are the first line of defense.
The body's last line of defense is the immune system. When infectious, foreign invaders penetrate the skin, the body attacks the invaders with its white blood cells, called leukocytes.
Lymphocytes, a form of leukocyte, play a large role in providing the body with its natural immunity to disease. They are produced in the bone marrow, spleen and thymus gland. They are carried throughout the body in the lymphatic system. It is a network of vessels similar to the body's system of blood vessels.
Lymph nodes lie along these lymph vessels. They receive the lymph through the lymph vessels and filter out microorganisms and other toxic agents. The lymph nodes are packed with lymphocytes.
Cancers cells can spread (metastasize) through the lymph vessels. Cancer cells can also be filtered out and caught in the lymph nodes.
Lymph nodes are bunched together in various parts of the body, especially the armpits, neck and groin. Infections and cancer from the ear, nose, mouth and throat drain into and cause swelling of nodes in the neck. The lymph nodes in the armpits collect from the upper chest and breasts.
The nodes in the groin collect material from throughout the lower body. They're particularly important in fighting infections and cancers that occur in the genital area.
Since enlarged lymph nodes can be caused by infections or cancer, it's important to be able to tell the difference. Here are some clues that help distinguish the two.
When an infection causes an enlarged lymph node, it typically grows very rapidly for a few days and is tender. As the infection subsides, the lymph node will decrease in size over the course of days to weeks but may not ever go back to normal size. The chances are that this is what's happened to you.
During this process calcium may be deposited in the node which then remains as a hard, movable, smaller lump. Rarely, abscesses will form in a lymph node and keep the node active and enlarged so it may be confused with cancer.
When cancer causes lymph node enlargement, it occurs over weeks, months and even years before it's noticed. It continues to grow over time.
So one of the ways to gauge if an enlarged lymph node is due to infection or cancer is for the person and/or health professional to track its size. It's also important to look for any obvious signs of cancer or infection in the parts of the body that drain into the area where the lymph node is located.