Pain under the left armpit may result from muscle damage or swollen lymph nodes due to an infection. However, it can also indicate a more serious problem, such as cancer or angina. The armpit is a ...

There are several causes of pain in the breast and armpit. Some of the most common causes include hormonal changes, an ill-fitting bra, or a muscle strain. Share on Pinterest Yauheni Rak/Getty Images ...

One in every eight women is afflicted with breast cancer during their lifetimes. This type of cancer is the most common among ...