According to BreastCancer.org, cancer is the result of mutations and abnormal changes in cells. Specifically, breast cancer occurs when the breast cells begin to grow in abnormal or uncontrolled numbers. (See Resource 1.) Breast cancer occurs in one out of every eight women, which is approximately 13 percent of the female population in the United States. It also occurs in approximately 2,000 men each year.
There are four stages of breast cancer, not including sub-stages. When the chest wall becomes involved, breast cancer is at usually at stage 3. At this stage, more specifically called 3C, there may not be any symptoms present.
Lumps occur in the breast or under the arm and can be indicative of the chest wall being affected by breast cancer.
Pain in the chest wall is usually localized to the affected section of the chest wall and can be felt beneath one or both breasts.
Many men and women may notice visible changes in the size of their breast or pectoral muscle region, as well as the skin or nipples, such as discoloration or changes in texture.
Discharge or bleeding can occur from the nipple and may occur without squeezing the affected nipple.