NEW YORK (CBSNewYork) – We’ve all seen glow in the dark posters, ink, and dyes usually lighting up under black light. Now, doctors are using glowing dyes to help find cancers during surgery and let doctors decide what to remove, and what to leave behind

When Dr. Sunil Singhal saw images of the tumor near Ryan Ciccozzi’s heart, he knew they had to act quickly.

“He had a very large tumor,” the doctor said. “It was almost four to five inches. So to give you a sense, it’s the size of two fists put together.”

Surgery has long been the best way to cure cancer. If the disease comes back, it’s usually because stray tumor cells were left behind.

But doctors have no good way during an operation to tell what is cancer and what is not. Now, they are testing dyes to make cancer cells glow and help surgeons see what to remove.

“Whatever is glowing needs to come out right now,” said Ciccozzi.

Dr. Singhal was inspired by the idea of glowing tumors about a decade ago. He found that when one dye was given in big doses by IV a day before surgery, it collected in cancer cells and glowed when exposed to near infrared light.

“So now, with the laser being on, you can now begin to see the difference,” he explained. “So this part is cancer and this is not.”

As the doctor operated on Ciccozzi, something unexpected showed up that didn’t appear in scans ahead of time.

“The cancer is now growing into the lung. So we’re going to take a piece of the lung out, too,” he said.

The dyes are still experimental, but several are in late-stage testing. The federal government is helping sponsor some of the research.

Paula Jacobs, an imaging specialist at the National Cancer Institute, thinks the dyes can dramatically improve patient care by helping to remove all of the cancer while sparing healthy tissue.

“Some cancers, it’s very much more important than others to not take any more than you have to,” she said.

Some experts think dyes may hold the most promise for breast cancer. Up to one third of women having a lump removed end up having a second surgery after tests later show that some cancer was left behind.

“This is a problem. It’s not only expensive, it’s debilitating, it’s upsetting, it’s all of these things,” said Jacobs. “And you know, patients have to undergo yet another surgery and sometimes even more than one.”

Dr. Singhal believes using the dyes and this technique could give patients a better chance of survival.

“Now it’s almost like we have bionic vision and we can start to scan the area, making sure that we removed everything,” he said.

Giving doctors a new way to hunt for hidden cancers.