Cancer localized to one part of the body is often difficult enough to treat, but tumors that are spreading take the challenge to another level.
Preventing the spread of tumors is a key target of cancer research, and a new device called a Cluster-Chip could help further this goal. By capturing clusters of tumor cells from patients' blood samples, this microchip, described in a paper published today in the journal Nature Methods, may be able to help doctors choose more effective treatments.
"The clusters are part of the fundamental process of how cancer spreads and kills people. To be able to isolate and analyze them is tremendously important not only to understand how cancer spreads but also to manage these patients," lead author Mehmet Toner, professor of surgery at Massachusetts General Hospital and the Harvard-MIT Division of Health and Sciences Technology, said in an interview.
Though the exact mechanism by which the clusters contribute to the spread of cancer remains unknown, prior work by Toner and his colleagues suggests they play a significant role.
"More clusters tend to correlate with worse clinical outcomes," says Toner. "They are found in metastatic cancer patients, those whose cancer spreads beyond the primary tumor, about 30 to 40 percent of the time."
This new microchip makes it possible to isolate and analyze these clusters of cancer cells with a simple, minimally invasive blood sample. As the blood flows through the chip, microscopic triangular posts funnel the clusters toward narrow channels that are too small for them to pass through.
"The clusters are very elastic and can move through the chip's 4,000 channels, or traps," says Toner. "If it is one cell, it can go by, but if it is a cluster, then it cannot."
Toner notes that further research will be necessary to determine how efficiently the chip captures the clusters. In addition, the chip still must go through the U.S. Food and Drug Administration's trials, so it will be several years at least until it can be used in a clinical setting. If approved, it could have applications for diagnosing, monitoring and treating cancer.
"It increases the ability to gain useful information about the cancer and allows us to use that information to guide treatment of patients," Toner says. "Ultimately, it can be used to break down the clusters with drugs to lower the chances of metastasis."
The results highlight the importance of the unique Cluster-Chip capture technique, and builds on prior microfluidic work.