When surgeons remove a tumor, the search for every last cancer cell is critical. The diseased tissue can be difficult to distinguish from the healthy.
Now researchers have developed high-tech goggles that allow doctors to see tumors glowing under infrared light. “As soon as they open the body, they will see the cancer tissue light up,” says Samuel Achilefu, the brains behind the goggles and a professor of radiology, biomedical engineering, biochemistry, and molecular biophysics at Washington University in St. Louis. “It’s clear what they need to take out.”
Inspired by night-vision glasses developed by the military, Achilefu came up with the idea about four years ago after listening to group of frustrated doctors discuss the problems of operating on patients using only static anatomic images. “They basically have to operate in the dark,” he says. “I thought, what if we create something that lets you see things that aren’t available to the ordinary human eye?”
Achilefu’s technology requires two steps: First, doctors inject a trace amount of an infrared fluorescent marker into the patient’s bloodstream. The marker, which is awaiting approval by the U.S. Food and Drug Administration, contains a peptide that locates cancer cells and gets trapped inside them due to a biochemical reaction. It takes roughly four hours for the tracer to flow through a patient’s entire body and clear from noncancerous tissue. After that, the operation may begin. Wearing the goggles, a doctor can inspect tumors under an infrared light that reacts with the dye, causing cancer cells to glow from within.
This month surgeons at the Washington University School of Medicine used the goggles on humans for the first time. So far, they have operated on four patients suffering from breast cancer or melanoma. “The [goggles] function fantastically,” says Ryan Fields, a surgical oncologist who is collaborating with Achilefu to hone and test the technology. “They allow us to see the cells in real time, which is critical.” Because the marker has not yet been FDA-approved, doctors are currently using a different, somewhat inferior marker that also reacts with infrared light.
Each year, 20 percent to 40 percent of women who have had breast cancer lumpectomies go back for second operations, according to Julie Margenthaler, a breast cancer surgeon who has also tested Achilefu’s goggles. “We’re talking about tens of thousands of women who have re-operations because we’re unable to see the microscopic extent of the tumors,” she says.
Margenthaler is delighted with the goggles, though she has advised Achilefu to make them lighter and with wireless connectivity. Once technical improvements are made and the marker gets FDA approval, doctors will perform tests to see whether the goggles help them improve results, reducing or eliminating the need for follow-up surgeries.
The goggles can be used to videotape operations and project them in real time, which may make them useful teaching tools. “You can’t get many students into the operating room, for example,” says Achilefu. They could also be used to train doctors in low-resource areas. “We would send them the goggles and then experts, say here at Washington University, could watch the operation on their iPhones and provide guidance.”
Achilefu does not yet know how much the goggles will cost. He says several unnamed companies have already expressed interest in licensing the technology, which he hopes will become available by the end of the year.
The team received a $2.8 million grant from the National Institutes of Health in 2012, but it has been a long road. Initially working on a tiny stipend from the Department of Defense, Achilefu spent years testing the technology on mice, rats, and rabbits, seeking to prove that his idea wasn’t merely science fiction. “Nobody would believe us until we showed that [the goggles] work,” he says.