For decades, doctors and breast cancer awareness campaigns have stressed the importance of early detection.
The how and when of early detection, though, is a more complicated matter.
Breast cancer screening guidelines keep changing and there’s some disagreement among doctors, especially when it comes to mammography.
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.
Promise of a Pill
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.
Helping Detect Breast Cancer
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.
Where the Research Goes from Here
The pill will have to be tested and approved by the FDA. Human trials have not yet been scheduled.
Thurber is optimistic about safety.
“Similar targeting molecules have gone through many clinical trials with very few side effects,” he said.
He noted the therapeutic trials used doses that were 100 times higher than what would be delivered for imaging.
“The fluorescent dye has also been used previously in humans,” Thurber added. “This dye has been conjugated to probes that bind to cancer cells after intravenous injection in cancer patients undergoing surgery. The surgeon can then detect and remove the fluorescent cancer cells. Because these trials have also shown no major toxicity, we believe the current conjugate will be well tolerated in humans.”
Thurber also explained that the probe was designed to target all types of breast cancer.
“In practice, it would likely be tested in women at higher risk first and then expanded to additional patients after the utility was established in the first group,” he said.
Thurber is also designing the agent to target aggressive tumors. This would make it easier to see the difference between slow-growing cancers or noninvasive breast cancers.
As for costs, Thurber said new technologies need to cover development costs and tend to be expensive at first.
Over time, however, he anticipates use of the new pill in imaging would cost less than an MRI. That’s because there’s no need for a specialized room, multi-million dollar equipment, or long scan times.
Long Way to Go
The research is promising, but there’s a long way to go.
Thurber believes mammography will continue as a breast cancer screening method for the foreseeable future.
The researchers also want to learn if this new technique could help detect other types of cancer. At the moment, it only detects tumors that are one to two centimeters deep.
“The main limitation is that the cancerous tissue must be near the surface of the body [for efficient detection of the light],” he said.
It may, however, be helpful in detecting other diseases.
“For example, rheumatoid arthritis is a debilitating disease of the joints, but there are effective treatments available,” said Thurber. “Since the damage caused by this disease is irreversible, early detection may enable us to start treatment before the patient experiences any symptoms.
“An inexpensive and easily implemented screening method, such as the one proposed here for breast cancer, may allow us to detect these preclinical cases of the disease and stop its progression before it even starts.”