Cancer can be difficult to treat. However, doctors from across the United States are developing glowing dyes that can highlight cancer cells, according to a new report.

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Sunil Singhal and his team from the University of Pennsylvania have been experimenting with a solution called ICG, which has been used for various medical purposes.

When it is given in big doses by IV the day before a surgery, it’s collected in the cancer cells and illuminated by infrared light. Dubbed TumorGlow, it’s now being tested for lung, brain and other types of tumors.

"It's almost like we have bionic vision," Singhal told the Associated Press. "We can be sure we're not taking too much or too little."

They are also trying out another, which binds to protein common in cancer cells. It produces similar effects for ovarian and lung cancers and has proved to be effective. In one study, it exposed 56 of 59 lung cancers seen on scans before surgery.

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Singhal isn’t the only one investigating dyes. Biotech companies Blaze Bioscience and Avelas Biosciences are also working on materials that can make cancer cells glow. Its products attach to a molecule that carries it to tumor cells in the breast, colon, head and ovaries.

“You can see it down to a few dozen cells or a few hundred cells,” Jim Olson of Blaze Bioscience said. “I've seen neurosurgeons come out of the operating room with a big smile on their face because they can see the cancer very clearly.”

While all of the dyes are currently still in the testing phase and will need to be approved by the Food and Drug Administration, the experts are hopeful.

“We think this is so important. Patients' lives will be improved by this,” said Paula Jacobs, an imaging expert at the National Cancer Institute. In five or so years, she predicts “there will be a palette of these.”

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