Primary breast cancer can 'shut down its own spread'

Breakthrough research shows that primary breast cancer has the ability to "essentially shut down its own spread." These findings may help "freeze" cancer cells before they get chance to form secondary tumors.

                         

Breast cancer cells (shown here) can break away from the original tumor and travel to the rest of the body. A new study shows how to stop them.

According to the National Cancer Institute (NCI), in the United States, a total of 266,120 women will be diagnosed with breast cancer in 2018.
Almost 41,000 of these cases will result in death.
However, as the NCI show, the number of breast cancer deaths has been steadily decreasing since the early 1990s.
Overall, the 5-year survival rate for breast cancer is now close to 90 percent.
After receiving a breast cancer diagnosis, a person's outlook is influenced by several factors — the most important of which is the extent of the cancer and whether it has spread beyond the original site of the tumor.
For instance, the 5-year survival rate for women with stage 2 breast cancer is approximately 93 percent. However, once the cancer has spread — or metastasized — this number drops to 22 percent.
As a result, more and more researchers have been focusing on the process of metastasis in the hope that a better understanding of it will lead to better strategies for prevention.
New research, published in the journal Nature Cell Biology, sheds such light on the process of metastasis in breast cancer, uncovering a previously unknown aspect of it.
Primary breast tumors, the new study shows, have the ability to stop themselves from spreading.
The scientists who conducted the research were jointly led by Dr. Sandra McAllister, from Brigham and Women's Hospital and Harvard Medical School, both in Boston, MA, and Dr. Christine Chaffer, from the Garvan Institute of Medical Research in Sydney, Australia.

Tracking down 'breakaway cancer cells'

With their team, Drs. McAllister and Chaffer conducted experiments in mice and human tumors. In a rodent model of breast cancer, they found that primary tumors have the ability to stop the "breakaway" cancer cells from traveling to other sites in the body.
The primary tumor does this by triggering an inflammatory response from the immune system. Once activated, the immune system dispatches "search patrols" of immune cells throughout the body. The main role of these cells is to find the locations where breakaway cells may be trying to settle and create new tumors.