Although immunotherapy – the ability to use the body’s immune system to fight off cancer – has not been as helpful for breast cancer patients, new research shows “promise” for some women, according to Dr. Patricia DeFusco, director of the Hartford HealthCare Cancer Institute Breast Program.
“Harnessing the immune system as a therapeutic tool has been more helpful with other cancers such as melanoma and kidney but studies such as this offer promise for a more prominent role for immunotherapy,” she says, referring to research conducted in Boston and Australia and published recently in the journal Nature Cell Biology.
The research, conducted in mice and human tumors, demonstrated that primary tumors have the ability to stop so-called cancer spread, in which cancer cells traveling through the blood stream or lymphatic system metastasize to other sites in the body. The primary tumor does this by triggering an inflammatory response from the immune system, which then sends immune cells throughout the body to fight off the cancer.
“For the most part, when a breast cancer metastasizes, it is no longer curable,” Dr. DeFusco explains. “We do not know exactly what triggers the metastatic process, nor do we know why only some cells that spread have the capacity to invade other tissues and form a metastatic focus or deposit.”
The latest research, she says, builds on what breast experts call the “abscopal effect,” in which treatment of a cancer focus at one site in the body can potentially cause regression of a cancer deposit at a distant site.
“It is thought to be due to release of mediators from malignant cells that elicit an immune response that can affect both the primary site and distant site. There have been models of this with the use of radiation and researchers at Memorial Sloan Kettering have looked at this experimentally by freezing primary breast cancers and then trying to simulate the immune system to amplify the immune response,” she says.
The research would apply to certain patients, specifically women with newly diagnosed lymph node positive breast cancer in which a finding of higher levels of the protein Interleukin 1-beta in tumor cells might suggest a better prognosis.
“The protein may inhibit metastatic cells from forming a cohesive unit, although the data is still in the experimental stages,” Dr. DeFusco says.
To learn more about research going on at The Cancer Center, including trials available to Hartford HealthCare patients as a result of the system’s membership in the Memorial Sloan Kettering Cancer Alliance, click here.