It can be difficult to see where a tumor starts and healthy tissue begins during an operation. But a new camera promises to make surgery to detect and remove cancer more successful.
German researchers have developed a camera that makes cancer cells glow in bright colors. They say it will help surgeons distinguish between the cancer and healthy tissues when removing a tumor during an operation. It may even make it easier for surgeons to remove the tumor entirely - rather than leaving tiny, hard-to-see cells.
"The camera makes tumor remnants or metastases that are millimeters in size, and which a surgeon might otherwise overlook, recognizable in detail," says Nikolaos Deliolanis of the Fraunhofer Institute for Manufacturing Engineering and Automation(IPA) in Mannheim.
Deliolanis heads the research group that developed the camera.
See more than the naked eye
This is how it works.
Before an operation, the doctor injects dyes into a patient's blood. The dyes are fluorescent molecules that carry antibodies designed to stick to tumor cells. They are currently being tested in clinical studies.
The molecules glow blue, green, red or another color - depending on the dye.
To see the colors, and whether they have attached to tumor cells, the surgeon illuminates the tissue, during the operation, with light set at a specific wavelength.
The camera superposes a normal color image with the image that shows any areas glowing with the fluorescent dye.
"The operator receives significantly more accurate information," Deliolanis says. "And patients operated under fluorescent light have improved chances of survival."
Left: Camera shows tissue marked with fluorescent dye. Right: Viewing the tissue without the new camera
The camera can detect up to four dyes at a time.
Injecting not only one but several dyes into the patient's blood and seeing how the tumor reacts could also possibly help to find out more about the biochemical structure of a tumor, says scientist Nikolas Dimitriadis, who has worked on the camera.
Detecting a brain tumor
"Seeing where the tumor ends and healthy tissue begins is especially important with malignant brain tumors," Dimitriadis says.
When operating brain tumors, a surgeon will aim to remove as little healthy tissue as possible, says Dimitriadis.
But if any of a brain tumor is overlooked - even the tiniest bit - it can become more aggressive and more deadly than the original tumor.
To help with brain tumor operations, the camera can detect a red dye already used in tumor surgery.
Physicians inject the substance 5-amino levulinic acid (5-ALA) into the patient.
The compound results in the patient producing a red dye in their cells. As tumors have an increased metabolism, they accumulate a higher amount of this dye than other cells and can be "unmasked."
Prototype presentation in two weeks
The camera is available for testing in surgery. The researchers will present a prototype at the Medica Trade Fair in Düsseldorf from November 20-23.
It's hoped the camera will soon be integrated into surgical microscopes or endoscopes.
"We plan to do our first clinical trials in 2014," Dimitriadis says, "to find out how suitable it is for clinics."
The trials will start by focusing on brain tumor surgery.