Imaging tests can’t tell whether a breast lump is cancerous. In the future, a fluorescent pill may make it possible to rule out cancer without doing a biopsy.

Current imaging methods are good at finding breast lumps. They can show where, how many, and how big they are.

The problem is that current imaging can’t differentiate between cancerous and noncancerous lumps.

In order to tell the difference, patients usually need a biopsy. The procedure is invasive, expensive, and less than 100 percent accurate.

False positives can lead to additional procedures and increased anxiety. There may also be higher healthcare costs and unnecessary treatment.

In an effort to make testing more accurate, researchers at the University of Michigan have found a way to improve existing imaging techniques.

The research team, led by Greg Thurber, Ph.D., an assistant professor of chemical engineering, developed an oral pill that lights up cancerous tumors.

The findings were presented at the 251st National Meeting and Exposition of the American Chemical Society.

The pill contains a dye that attaches to cancer cells or blood vessels only found in tumors.

The dye fluoresces under near-infrared light. The tumors light up so they stand out from surrounding tissue. There is no need for a needle or ionizing radiation.

The research was conducted using mice and has not yet been tested in humans.

In an email interview with Healthline, Thurber described what this research might mean for people.

“We envision that a patient would take the pill at home a day or two before their appointment and then come in to the office for screening. The fluorescence imaging could be done by itself, but a more powerful application would be to pair it with ultrasound,” he said.

Thurber explained that ultrasound is safe because it doesn’t use any ionizing radiation and it’s relatively inexpensive. Ultrasound can produce a detailed image of a lesion. It can’t tell if it’s cancerous.

Fluorescence imaging shows if a lesion is cancerous, but the images can be blurry. According to Thurber, that’s due to the scattering of light in the breast tissue.

Fluorescence imaging from the pill and ultrasound imaging are complementary, said Thurber.

“By combining the two, the molecular information can be overlaid with the ultrasound image for a more precise view,” Thurber explained.

It’s a combination that could prove very helpful to women with dense breast tissue, which makes it more difficult to see cancer.

The pill will have to be tested and approved by the FDA. Human trials have not yet been scheduled.