What could this be-Cyst or Lymph Node?

Lymph nodes are a part of human immune system. They make antibodies which keep you from being infected from same bacteria or virus again. When it is enlarged it is usually caused by some kind of infection. Cyst is also possible to show in armpit. It can be due to infection caused by antiperspirants in addition with deodorants. It is very hard to tell the difference and to do so you must visit the doctor to determine what it is. It is important because of treatment.

Hi, I must ask some questions. Yesterday while I was showering I have noticed some little knot in my armpit. I have never seen it before or maybe I did not notice it. It is under the skin, look like a small pill and it hurts when I touch it. My girlfriend says that it could be cyst or lymph node. Which one is it? What lymph node is exactly?

Lymph nodes are a part of human immune system. They make antibodies which keep you from being infected from same bacteria or virus again. When it is enlarged it is usually caused by some kind of infection. Cyst is also possible to show in armpit. It can be due to infection caused by antiperspirants in addition with deodorants. It is very hard to tell the difference and to do so you must visit the doctor to determine what it is. It is important because of treatment.