Breast pain can be cyclical and related to your menstrual cycle or noncyclical and not related to your cycle. This pain affects 50 to 70 percent of women and has a number of possible causes. Learn Author: Jaime Herndon And Rachel Nall. Breast pain is any discomfort, tenderness, or pain in the breast or underarm region, and it may occur for a number of reasons. Generally, breast pain is not a sign of breast cancer.. Should breast pain cause me to be concerned about breast cancer?