Breast cancer mostly affects women, but men can develop it too—though it’s far less common.
Cancer occurs when cells grow uncontrollably, forming tumors. However, not all breast lumps are cancerous. Many are benign (non-cancerous) tumors, which may not spread or pose a serious threat. Still, some benign lumps can increase the risk of developing breast cancer in the future. That’s why any breast lump or change should be checked by a healthcare professional to determine if it’s benign or malignant (cancerous).
Where Does Breast Cancer Start?
The breast is made up of glands, ducts, and fatty tissue, and cancer can start in different areas:
Lobules – These are the milk-producing glands, and cancer that starts here is called lobular carcinoma.
Ducts – These carry milk to the nipple, and most breast cancers begin here. This type is called ductal carcinoma.
Nipple – This is where the ducts merge and exit the breast. A rare cancer known as Paget’s disease can start in the nipple.
Fat & Connective Tissue (Stroma) – These provide structure and support for the breast. A rare tumor called phyllodes tumor can begin here.
Blood & Lymph Vessels – The breast also contains blood and lymphatic vessels, where a rare cancer called angiosarcoma can form.
Some less common cancers can start in other tissues, such as sarcomas and lymphomas, but they are not typically classified as breast cancer.
