Even when certain types of cancer are fairly easy to treat, doctors often don't detect them until it's too late. But a new type of ultra-sensitive test might change that. A shot of nanoparticles would be designed to travel through your body looking for tumors that other tests might miss. An hour later, you could pee on a simple paper test and get the results.
"Even using the best tools we have available, we can't find some cancers until 10 years after they've started growing, when they are some 50 million cancer cells strong," Sangeeta Bhatia, a doctor and medical engineering professor at MIT, told a crowd at TEDMED.
Bhatia and her team have engineered cancer-detecting nanoparticles that are 1,000 times smaller than the width of a human hair—just the right size to slip into a tumor. "It turns out that the blood vessels of many tumors are leaky, so the nanoparticles can leak out," she said. "That means as an engineer, depending on how big or small I make a material, I can change where it goes in your body."
Here's an animation of the tiny blue particles slipping inside a tumor:
Inside a tumor, the tiny particles react with enzymes to signal that there's a problem. Then, because they're small enough to go through the kidney, they come out with urine and can be engineered to show up on different types of tests, including something that's as easy and cheap to make as a pregnancy test.
In the lab, the researchers have already succeeded in using the nanoparticles the lab on mice to detect lung cancer, ovarian cancer, and colon cancer in mice. Now they're working on making it cheap to manufacture at scale and will have to show that it's safe to work in humans. Bhatia thinks it will eventually save lives—maybe especially in the developing world, where it's harder for a patient to get a biopsy sent to a lab.
"I dream that one day instead of going into an expensive facility for screening for colonoscopy, for mammograms, for Pap smears, that you could get a shot, wait an hour, and do a urine test on a paper strip," she said. "I imagine that this could happen even without the need for steady electricity or a medical professional in the room—maybe they would be far away and connected only by the image on a smartphone."