DURHAM, N.C. – When caught early, breast cancer can be a curable disease. But doctors say years after treatment, the cancer can return in the bones. Then it is often deadly. What’s next is promising research.

More than six years ago Ivette Marrero was diagnosed with breast cancer. She went through chemo, radiation and reconstructive surgery. But, last summer, after she began having pains, doctors gave her the devastating news. The cancer had spread to her bones.

“At that point it’s considered terminal cancer and it’s nothing they can do,” Marrero said.

She’s not alone.

Doctors say when hormone-positive breast cancer spreads, it generally goes to the bones.

Dr Dorothy Sipkins, an associate professor at Duke Health said, “The issue that we face in breast cancer is that most patients who die from the disease are dying because of this distant relapse.”

Researchers at Duke learned that breast cancer cells can be found in bone marrow even in very early stages of breast cancer.

“Cells can break away get into the blood stream and travel to other sites in the body,” Sipkins said. “Cells are going to the bones so early in the disease process and then lying dormant there for extended periods.”

But now, through experiments in mice, researchers say they’ve figured out why those cancer cells end up in the bone marrow, and how to get them out using drugs.

“We could block the circulating breast cancer cells form coming in and we could force the cells that were already in the bone marrow back out the door again into the blood stream,” Sipkins said.

Once in the blood stream researchers hope it will be easier to target the cancer cells and kill them.

Right now the research has only been done in mice, but human trials are expected to begin in the next few years.

“Research is very important because I think we are so close. It is so close every day,” Marrero said.

She has tried experimental treatments and says these findings from Duke give her hope – even if they never benefit her directly.

“If it’s not me,” she said, “it will be for my daughters.”