Breast cancer is a type of cancer that originates with the proliferation of cells in the breast tissue. Breast cancer is the most prevalent cancer diagnosed among women in the United States, second only to skin cancer. However, breast cancer does not affect only women. Everyone is born with breast tissue, so anyone can develop breast cancer.

Breast cancer symptoms can include:

• A breast lump or thicker skin that feels different from the rest of the tissue.
• A nipple that seems flattened or turned inward.
• Color changes in breast skin. Breast skin that is white may seem pink or red. In those with brown or black skin, the breast skin may appear darker or redder than the rest of the chest skin.
• Changes in breast size, shape, or appearance.
• Changes in the skin around the breast, such as dimpled or orange peel-like skin.
• Peeling, scaling, crusting, or flaking skin on the breast. 

The specific cause of the majority of breast cancers remains unknown. Researchers discovered factors that raise the chance of breast cancer. Hormones, lifestyle choices, and environmental factors all fall under this category.

Breast cancer develops when something affects the DNA inside cells in the breast tissue. A cell’s DNA contains the instructions that inform the cell what to do. In healthy cells, the DNA instructs them to grow and multiply at a certain rate. The instructions direct the cells to die at a predetermined time. Cancer cells’ DNA alterations provide new instructions. The alterations instruct cancer cells to rapidly multiply. Cancer cells can survive when healthy cells die. This leads to an excess of cells.

Cancer cells may develop a lump known as a tumour. The tumor can spread to invade and destroy healthy body tissue. Cancer cells might eventually separate and travel to other regions of the body. Metastatic cancer is the term used to describe cancer that has spread. The DNA mutations that cause breast cancer typically occur in the cells that border the milk ducts. Breast cancer that begins in the ducts is referred to as invasive ductal carcinoma. Breast cancer can potentially develop from milk gland cells. Invasive lobular carcinoma refers to cancer of the lobules. Other breast cells can become cancerous, but this is uncommon.

Breast cancer survival rates have been improving. The number of people dying from breast cancer is steadily decreasing. This is largely due to strong support for breast cancer awareness and research funding.

Advances in breast cancer screening enable doctors to discover the disease earlier. Finding the cancer early increases the likelihood that it will be cured. Even when breast cancer cannot be cured, there are numerous treatments available to help patients live longer. New findings in breast cancer research assist healthcare providers in selecting the most successful treatment regimens.