Even when cancer patients have had a tumor removed, cancer cells can spread to other parts of the body and develop cancer in a new location. To prevent this, researchers have developed an implant that can trap cancer cells as they spread, preventing them from settling in a new organ.
Known as metastatic cancer, this spread of cancer cells can establish a cancerous tumor in a new site. These cancer cells usually travel through the bloodstream, but they may also use the lymph system, binding to a lymph vessel to travel to a new location. Once there, the cancer cells can spread, forming a tumor in a different organ than the one that was originally affected by cancer.
These traveling cancer cells may circulate throughout the body in low numbers over a long period of time before they establish in a new location. What this means is that cancer patients may think they have successfully dealt with their tumor and beat the disease, but their cancer then reestablishes in a new location later on. To give these patients the best chance for survival, doctors need to catch these circulating cancer cells as early as possible. However, they can be difficult to detect.
Knowing what a danger metastatic cancer can be to recovering cancer patients, professor Lonnie Shea of Northwestern University Feinberg School of Medicine in Evanston, Illinois, breast cancer surgeon Jacqueline Jeruss, and colleagues set out to find a solution. They published the results of their experiment in the journal Nature Communications.
The researchers used poly(lactide-co-glycolide), or PLG, to create a biomaterial implanted scaffold. The material is already approved and used for various medical uses. They also included a signaling molecule called CCL22 which attracts certain immune cells with the cancer cells following along. The scaffold is meant to identify and capture metastatic cancer cells circulating through the body, trapping them before they can become established in an organ.
To test their implant, the researchers inserted two implants about 5 mm (0.2 inches) in diameter into the abdominal fat or under the skin of mice with metastatic breast cancer. Eight mice were used in the study. The researchers then used inverse pectroscopic optical coherence tomography (ISOCT), an imaging technique, to see what healthy cells or cancer cells were trapped by the implant. The cancer cells could be identified by their greater density.
The results of the trial were encouraging. The researchers found that the implants did successfully capture cancer cells that were circulating in the bloodstream of the mice, and they saw results in just two weeks. This means that the captured cancer cells were not able to travel to a new location and establish a cancerous tumor. The team compared the mice with implants to a group of mice that did not receive implants, and found that the implanted mice had many less cancer cells in their lungs.
Although the researchers have only tried their implant in mice so far, they believe it should work the same way in humans. They are hoping to soon perform human trials of the device. If successful, the researchers believe the implant could help detect metastatic cancer earlier as well as help prevent new tumors from forming. This could help cancer patients delay any new cancers from developing.
With current technology, doctors and their patients often do not know cancer has spread until the patient develops symptoms. By then, the cancer has established in a new location and requires aggressive treatment. If an implant could detect the traveling cancer cells earlier, as well as help prevent their spread, it could help doctors treat the disease earlier and improve the chance of the patient beating the disease.