ORLANDO, Fla. (Ivanhoe Newswire) – Breast cancer is one of the most common types of cancer. Each year, about 2.3 million people in the world develop the disease. Catching breast cancer early is critical for survival. That’s why researchers are studying how breast cancer spreads in the body. They’ve uncovered some interesting clues about when the cancer travels in the body.

About one in every eight women will develop breast cancer during her life. 

Kristen Lyons  says, “I just, I felt something and I thought, huh, it was real tiny, but it just felt different.”

Kathleen DePalo says, “I was never one for self-examination, and that was a big mistake.”

When breast cancer is found early, it’s highly treatable. But if it’s spread, or what doctors call “metastasized”, the prognosis isn’t so good.

“So, we understand metastatic breast cancer, it’s not curable.”  explains Sara Hurvitz, MD, UCLA/Jonsson Comprehensive Cancer Ctr.

Scientists know metastasis happens when circulating cancer cells break away from the original tumor and travel in the body via blood vessels. Until now, researchers assumed tumors released cells continuously and haven’t known much about when tumors spread.

In a new study published in the Journal Nature, Swiss researchers examined mice and female cancer patients. They found circulating cells that later form metastases mainly arise during sleep. In other words: when a person or animal is asleep, the tumor seems to “wake up.” Cells that leave a tumor at night also seem to divide more quickly compared to cells that exit in the daytime. Researchers say this isn’t just an interesting finding, it could help improve the way breast cancer is diagnosed and treated in the future. For instance, the next step is to see if giving patients therapies at different times of the day has an effect on outcomes. New information that could change how doctors manage women with breast cancer.

The researchers say these findings suggest that the escape of circulating cancer cells from the tumor may be controlled by hormones, such as melatonin, which determine a person’s rhythms of day and night. They say more studies are needed to determine how to put this discovery into practice.

Contributors to this news report include: Julie Marks, Producer; Roque Correa, Editor.