Types of Breast Cancer

Breast cancer is a disease that is becoming more and more common nowadays and is increasingly harmful to women. Many well-known women have even lost their precious lives due to breast cancer. Therefore, female friends should have a certain understanding of breast cancer. So, what are the common types of breast cancer? Below, we will introduce you to some relevant knowledge about breast cancer!

1. Overview of Breast Cancer

Breast cancer is one of the most common malignant tumors in women. According to statistics, its incidence rate accounts for 7-10% of all malignant tumors in the body, second only to uterine cancer in women. Its onset is often related to genetics, and the incidence rate is higher in women between 40 and 60 years old and before and after menopause. Only about 1-2% of breast cancer patients are men. In order to better treat breast cancer, breast cancer is often staged clinically.

2. Classification of Breast Cancer

1. Breast ductal carcinoma

This is a type we often see in clinical practice. This cancer has no localized location and can grow outside or near the duct. However, the cancer cells are confined to the ducts, where they can be arranged in solid, cribriform, low papillary or tubular shapes and are no longer classified into subtypes.

2. Invasive ductal carcinoma

This type is a common form of the disease, and at the time of diagnosis, the cancer has already spread beyond the periductal structures and ductal dilatation, becoming a transformed cancer.

This type of cancer mostly occurs in the lobules, and the enlargement of the lobules will show obvious thickening and will be filled with cancer cells. In addition, the cancer cells are slightly larger in size, more uniform in shape and size, and have richer cytoplasm, and are usually called lobular carcinoma in situ.

3. Breast cancer staging

Breast cancer can be divided into stages 0 to 4 based on the size and spread of the tumor. The following are definitions of breast cancer stages:

Early stage or stage 0 breast cancer: This means that the tumor is confined to one place and no tests have proven that it has spread to the lymph nodes. (i.e. carcinoma in situ)

Stage 1 breast cancer: The cancer mass is ≤ 2 cm and has not spread.

Stage 2A breast cancer: refers to a mass less than 2 cm with lymph node infiltration or a mass greater than 2 cm but less than 5 cm with no lymph node infiltration.

Stage 2B breast cancer: refers to a tumor that is larger than 5 cm and the cancerous tumor has not yet infiltrated the axillary lymph nodes, or a tumor that is larger than 2 cm and smaller than 5 cm and is accompanied by lymph node infiltration.

More advanced breast cancer (metastatic) means the cancer has spread to the lymph nodes and other parts of the body.

Stage 3A breast cancer: also known as high-stage breast cancer, refers to a tumor > 5 cm, the cancerous tumor has infiltrated the axillary lymph nodes or no matter how large the tumor is, the cancerous tumor has spread to another tissue or adjacent tissue.

Stage 3B breast cancer: Regardless of the size of the tumor, it has already spread to the skin, chest wall, or internal mammary lymph nodes (limited to the area under the breast and inside the chest cavity).

Stage 3C breast cancer: Regardless of the size of the tumor, it has extensively invaded the lymph nodes.

Stage 4 breast cancer: This is defined as a tumor of any size that has spread to sites away from the breast, such as the lungs, liver, brain, or distant lymph nodes.