5. Swelling under the arm
Though a lump is one of the most obvious signs of breast cancer, in some cases, a lump may not be able to feel in the breast, but rather underneath the arm. If you notice a lump in your armpit, it could be an indication that you have breast cancer. There are several lymph nodes located throughout the body, including the armpits.
When cancer progresses, it is not uncommon for it to spread into the lymphatic system. If this happens, the lymph nodes will likely become inflamed. A lump under the armpit is not always a sign of breast cancer, however; there are several other things that can cause a lump in this area, including irritation from shaving (an ingrown hair), a cyst, a reaction to antiperspirant, or an infection. Nevertheless, if you do spot a lump in your armpit, having an exam is crucial.