London: Scientists in Germany claim to have developed a "microchip sensor" that can be implanted close to a tumour to monitor its growth.
A team at the Technical University in Munich, which has developed the sensor, says that the device can track and treat tumours that are difficult to reach, or better left alone in patients.
In fact, it tracks oxygen levels in nearby tissue to detect if a tumour is expanding; results are then transmitted wirelessly to a patient`s doctor, reducing the need for frequent hospital scans.
The sensor is implanted next to a tumour, and measures the concentration of dissolved oxygen in nearby tissue fluid.
If this drops it can indicate aggressive growth, and doctors can be alerted.
"The microelectronic chip has a set of electrodes that detect oxygen saturation. It transmits this sensor data to an external receiving unit that`s like a small box you carry around in your pocket.
"From there it goes into the doctor`s computer, and they can look at the data and decide whether the tumour activity is getting worse," said team leader Sven Becker.
The scientists believe this will reduce the need for frequent hospital check-ups. "Normally you would have to go to the hospital to be monitored -- using machines like MRI to detect the oxygen saturation.
With our system you can do it on the go," Becker said. Future designs will include a medication pump that can deliver drugs directly to the affected area, which will lead to less aggressive and more targeted cancer treatments, say the scientists.
"There are some tumours which are hard to remove -- for example, close to the spine. You run the risk of cutting the nerve if you remove them surgically. Or the problem may be that the tumour is growing slowly. In these cases it`s better to monitor the tumour, and only treat it if there`s a strong growth phase," Becker said.
The team plans to add a medication pump to the chip that can release chemotherapeutic drugs close to a tumour if treatment is needed. They say this will prove more effective and less toxic for future cancer patients.
"In traditional chemotherapy you put drugs into the whole body -- which can have awful side effects. We want to add a pump to our chip, so if the sensor detects growth, you can apply microscopic amounts to tumour," he said.