The first sign of breast cancer is often a painless lump. However, early breast cancer is often found on a mammogram before a lump can be felt.

Other symptoms of breast cancer may not appear until the cancer is more advanced. These include:

• A thickening in the breast or armpit.
• A change in the size or shape of the breast.
• Changes in the skin of the breast, such as a dimple or skin that looks like orange peel.
• A change in the nipple, such as scaling of the skin, a nipple that turns in, or discharge or bleeding.
• A change in the color or feel of the skin around the nipple (areola).

About one percent of breast cancer occurs in men. Although most men diagnosed with breast cancer are older than 65, the disease can appear in younger men. For this reason, any breast lump in an adult male is considered abnormal.

Inflammatory breast cancer is a specific type of breast cancer that involves the skin of the breast. It occurs when breast cancer cells form "nests" and block the lymphatic drainage from the skin of the breast. Symptoms include redness, tenderness, and warmth. Thickening of the skin of the breast (an orange-peel appearance), rapid breast enlargement, and ridging of the skin of the breast may also be present. Some women may also develop a lump in the breast.