Overview — The Lymphatic System

The lymphatic system is an intricate network of organs, tissues and vessels that aid in the body’s defense against foreign cells, toxins and cancer cells. Basic knowledge of this system will help in understanding its involvement in the development of metastatic breast cancer.

In the breast and axilla, fluid called “lymph” is released by blood vessels into the surrounding breast tissue. Lymph is collected by lymphatic vessels and transported to “filtering stations” called lymph nodes. Lymph is filtered and then transported back into the blood stream via veins.

When cancer cells begin growing out of control, they may break away from the main mass of the tumour and enter the lymphatic vessels. Tumour cells may spread from lymph node to lymph node and travel via the lymphatic system to the blood stream and onto other parts of the body.