The lymph (lymphatic) system of the breast

The lymph system is important to understand because it is one of the ways that breast cancers can spread. This system has several parts.

Lymph nodes are small, bean-shaped collections of immune system cells (cells that are important in fighting infections) that are connected by lymphatic vessels. Lymphatic vessels are like small veins, except that they carry a clear fluid called lymph (instead of blood) away from the breast. Lymph contains tissue fluid and waste products, as well as immune system cells. Breast cancer cells can enter lymphatic vessels and begin to grow in lymph nodes.

Most lymphatic vessels in the breast connect to lymph nodes under the arm (axillary nodes). Some lymphatic vessels connect to lymph nodes under the breast bone (internal mammary nodes) and either above or below the collarbone (supraclavicular or infraclavicular nodes).

If the cancer cells have spread to these lymph nodes, there is a higher chance that the cells could have also gotten into the bloodstream and spread (metastasized) to other sites in the body. The more lymph nodes with breast cancer cells, the more likely it is that the cancer may be found in other organs as well. Because of this, finding cancer in one or more lymph nodes often affects the treatment plan. Still, not all men with cancer cells in their lymph nodes develop metastases to other areas, and some men can have no cancer cells in their lymph nodes and later develop metastases.

Information for men with breast cancer

Symptoms of Male Breast Cancer

Causes of male breast cancer

What are the risk factors for breast cancer in men?

Diagnosis and Tests of male breast cancer

The Pathology Report (Male Breast Cancer)

Treatment & Stages of male breast cancer

Coping and support for male breast cancer