Hello,

We noticed you're browsing in private or incognito mode.

To continue reading this article, please exit incognito mode or log in.

Not an Insider? Subscribe now for unlimited access to online articles.

Rewriting Life

New Implant Can Monitor Tumors Continuously

Researchers hope to combine the sensor with a device to deliver targeted chemotherapy.

A team of medical engineers in Germany has developed an implant to continuously monitor tumor growth in cancer patients. The device, designed to be implanted in the patient near the tumor site, uses chip sensors to measure oxygen levels in the blood, an indicator of growth. The data is then transmitted wirelessly to an external receiver carried by the patient and transferred to his or her doctor for remote monitoring and analysis.  

Sensing oxygen: This implantable sensor measures the concentration of dissolved oxygen in tissue, an indicator of tumor growth.

“We developed the device to monitor and treat slow-growing tumors that are difficult to operate on, such as brain tumors and liver tumors, and for tumors in elderly patients for whom surgery might be dangerous,” said Helmut Grothe, head of sensor technology at the Heinz-Nixdorf Institute for Medical Electronics at the Technical University of Munich.

The roughly two-centimeter-long device, dubbed the IntelliTuM (Intelligent Implant for Tumor Monitoring), includes a self-calibrating sensor, data measurement and evaluation electronics, and a transmitter. All the components are contained within a biocompatible plastic housing.

The device sensor detects the level of dissolved oxygen in the fluid near the tumor; a drop in that measure suggests the metabolic behavior of the tumor is changing, often in a more aggressive way. So far, researchers have tested the device in tissue grown in culture. The next step is to test it in live animals.

Most monitoring of tumor growth is currently done via CT scans, MRI, and other forms of external imaging. “The advantage of an implant over external imaging is that you can monitor the tumor on the go,” says Sven Becker of the Technical University of Munich. “This means patients would have to pay fewer visits to the hospital for progression and postsurgery monitoring of tumors. They also wouldn’t have to swallow contrast agents.”

In addition to the oxygen sensors, researchers have equipped the device with sensors to monitor pH, another indicator of tumor growth. The oxygen sensors can be calibrated inside the body, though the researchers have not yet developed this capability with the pH sensors.

The team also plans to incorporate a miniature medication pump that can be set to deliver chemotherapy directly into the tumor environment, if and when the monitoring chips show that the tumor has become more aggressive.

It’s still not clear who will be the best candidates for this type of device. “Most folks who are not good candidates for [tumor removal] surgery will not want surgery to implant this so that they can be monitored,” warns Eugene Woltering, professor of surgery and neurosciences at the Louisiana State University Health Sciences Center.

Woltering, who was not involved in the research, does believe the device may be ideal for those for whom complete surgical removal of the tumor is impossible or not desirable.

“Those individuals could have these implanted in sites where we left tumor behind to act as an early warning system,” Woltering said. “If it could drip some chemo in the affected area, then the local concentration of chemo would far exceed the diluted chemo concentration that would otherwise reach the tumor in the blood’s total volume.”

Want to go ad free? No ad blockers needed.

Become an Insider
Already an Insider? Log in.
More from Rewriting Life

Reprogramming our bodies to make us healthier.

Want more award-winning journalism? Subscribe to Insider Plus.
  • Insider Plus {! insider.prices.plus !}*

    {! insider.display.menuOptionsLabel !}

    Everything included in Insider Basic, plus the digital magazine, extensive archive, ad-free web experience, and discounts to partner offerings and MIT Technology Review events.

    See details+

    Print + Digital Magazine (6 bi-monthly issues)

    Unlimited online access including all articles, multimedia, and more

    The Download newsletter with top tech stories delivered daily to your inbox

    Technology Review PDF magazine archive, including articles, images, and covers dating back to 1899

    10% Discount to MIT Technology Review events and MIT Press

    Ad-free website experience

/3
You've read of three free articles this month. for unlimited online access. You've read of three free articles this month. for unlimited online access. This is your last free article this month. for unlimited online access. You've read all your free articles this month. for unlimited online access. You've read of three free articles this month. for more, or for unlimited online access. for two more free articles, or for unlimited online access.