PITTSBURGH (KDKA) – When it comes to treating some cancers, one of the toughest things after a procedure is making sure all the cancer cells are gone.

invisible cells can still lurk inside the body.

Now, a new test may be able to make the invisible – visible.

“Green glow” could light up the future of cancer therapy.

“I feel like I’m a miracle woman and I’m lucky,” Francie Howat said.

Howat was diagnosed with lung cancer earlier this year.

The 65-year-old lifelong smoker, was scared and worried that she wouldn’t be around to watch her grandchildren grow up.

She decided to be part of a research trial at Penn Medicine at the University of Pennsylvania.

Dr. Sunil Singhal said that up to 50 percent of the time when lung cancer is surgically removed, invisible cancer cells are missed and the disease can reoccur.

Now, it’s been found that a dye, called ICG, can make the invisible–visible.

It can accumulate in lung cancer cells and then light up green under infrared light.

“For the first time, we actually have the ability to make tumors glow,” Dr. Singhal said.

Before the operation, patients are injected with the dye.

During the surgery, the light is turned on.

With Howat, tissue that looked normal and was clear on CT scans was actually cancerous.

If the testing in lung cancer pans out, researchers are hoping the procedure can be adapted to find other cancers.

Howat was able to avoid chemo and radiation.

Now, she’s dancing with her grandchildren to celebrate and recovering from a remarkably short stint with lung cancer.

“He said it would have killed me. I think that’s laying it on the line,” Howat said.

So far, the green dye has only been tested on five lung cancer patients and results are promising.

Doctors at the University of Pennsylvania are still tweaking the process and hope to expand the research soon.

Dr. Maria Simbra