Invasive Breast Cancer: NCCN Guidelines for Patients
The NCCN Guidelines for Patients were developed by the National Comprehensive Cancer Network (NCCN). NCCN is an organization that unites leading cancer care centers in the United States of America. Its activities are focused on scientific research, treatment and education of patients.
Breast cancer basics
Anyone can develop breast cancer. Invasive breast cancer is cancer that has spread from the milk ducts or milk glands into the breast tissue or nearby lymph nodes.
The breast
The breast is an organ and a gland found on the chest. The breast is made of milk ducts, fat, nerves, lymph and blood vessels, ligaments, and other connective tissue. Behind the breast is the pectoral (chest) muscle and ribs. Muscle and ligaments help hold the breast in place.
Breast tissue contains glands that can make milk. These milk glands are called lobules. Lobules look like tiny clusters of grapes. Small tubes called ducts connect the lobules to the nipple to deliver breast milk. The ring of darker breast skin is called the areola. The raised tip within the areola is called the nipple. The nipple-areola complex (NAC) is a term that refers to both parts.
Lymph is a clear fluid that gives cells water and food. It also helps to fight germs. Lymph drains from breast tissue into lymph vessels and travels to lymph nodes near your armpit (axilla). Nodes near the armpit are called axillary lymph nodes (ALNs).
Breast cancer
Breast cancer starts in the cells of the breast. Almost all breast cancers are carcinomas. Carcinomas are cancers that start in the cells that line the inner or outer surfaces of the body.
There are different types of breast carcinoma. The most common types are either ductal or lobular.
- Ductal carcinoma starts in the cells that line the milk ducts. Milk ducts are thin tubes that carry milk from the lobules of the breast to the nipple. It is the most common type of breast cancer.
- Lobular carcinoma starts in the lobules (milk glands) of the breast.
Anyone can develop breast cancer, including males. Although there are some differences between males and females, treatment is very similar for all genders.
How breast cancer spreads
Cancer cells don’t behave like normal cells. Cancer cells differ from normal cells in the following ways.
Primary tumor
Over time, cancer cells form a mass called a primary tumor.
Invasive
Cancer cells can grow into surrounding tissues. Invasive breast cancer is breast cancer that has spread from the milk ducts or milk glands (lobules) into the breast tissue or nearby lymph nodes.
Metastasis
Unlike normal cells, cancer cells can spread and form tumors in other parts of the body. Cancer that has spread to other organs is called a metastasis. In this process, cancer cells break away from the first (primary) tumor and travel through blood or lymph vessels to distant sites. Once in other sites, cancer cells may form secondary tumors.
- Cancer that has spread to a nearby body part, such as the axillary lymph nodes, is called a local metastasis. It might be referred to as local/regional disease or locally advanced disease.
- Cancer that has spread to a body part far from the primary tumor is called a distant metastasis.
Breast cancer can metastasize almost anywhere, but most commonly spread to the bones, lungs, liver, spine, or brain. Breast cancer that has metastasized to other parts of the body is still called breast cancer.
For more information on metastatic breast cancer, read the NCCN Guidelines for Patients: Breast Cancer – Metastatic, available at NCCN.org/patientguidelines.
For more information on metastatic breast cancer, read the NCCN Guidelines for Patients: Breast Cancer – Metastatic, available at NCCN.org/patientguidelines.
Key points
- Anyone can develop breast cancer.
- Inside breasts are lobules, ducts, fat, blood and lymph vessels, ligaments, and connective tissue. Lobules are structures that make breast milk. Ducts carry breast milk from the lobules to the nipple.
- Breast cancer often starts in the ducts or lobules and then spreads into the surrounding tissue.
- Invasive breast cancer is cancer that has grown outside the ducts or lobules into surrounding tissue. Once outside the ducts or lobules, breast cancer can spread through lymph or blood to lymph nodes or other parts of the body.
- Metastatic breast cancer has spread to distant sites in the body.
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You can read more about Invasive Breast Cancer, its treatment methods and follow-up after treatment in the full text of the recommendations for patients by downloading it below.