Medical Device Daily

Like many researchers, Vadim Backman, PhD, a professor of biomedical engineering at Northwestern University (Evanston, Illinois), had some existing data from previous work — in this case concerning colon cancer. And he also had a hypothesis — that optical technology he developed also could be used to detect early cancerous lesions in the pancreas by examining tissue near the pancreas, rather than the actual organ itself.

That early research, combined and further tuned by the hypothesis, has resulted in a paper in the Aug. 1 issue of Clinical Cancer Research, a journal of the American Association for Cancer Research (AACR; Philadelphia), indicating the possible use of optical technology for better detection of pancreatic cancer.

Pancreatic cancer, which is expected to lead to the deaths of 33,000 Americans in 2007, is considered particularly lethal because it is so difficult to detect at an early stage, which is critical to successful treatment.

“We were already working with colon cancer, and we were thinking this would work well in pancreatic cancer – it’s the most deadly cancer, actually,” Backman told Medical Device Daily .

Then, in conversations with Leon Esterowitz of the National Science Foundation (Arlington, Virginia), which provided funding for the study, Backman was urged to look at the optical technique in pancreatic cancer.

The optical technology exposes cellular changes indicative of cancer in tissue near the pancreas.

“We were so encouraged by the successes with colon cancer that we decided to drive the research in a new direction,” Esterowitz said in a statement. “With colon cancer, you have time, even years, to treat it successfully. Unfortunately, for pancreatic cancer, it is not only critical to detect it early, or even before it becomes cancerous, but in many cases it really is the only hope.”

The technologies are named four-dimensional elastic light-scattering fingerprinting (4D-ELF) and low-coherence enhanced backscattering (LEBS) spectroscopy. The light-scattering technique hinges on the “field effect” of pancreatic cancer, that is, where cancerous tissue exerts subtle physical changes in surrounding tissue, according to the AACR.

Specifically, the researchers looked at the field effect in the duodenum, the upper part of the small intestine, by using upper endoscopy, a minimally-invasive procedure that entails the placement of an endoscope down the throat and to the stomach to the duodenum.

The instrument shines an intense white light onto a tissue sample and then measures how cellular structures on the micro- or nanoscale refract the light, causing it to scatter in different directions, according to the AACR. Computer analysis of the scatter patterns then are used to determine if these cellular structures are different than those seen in structures in normal tissue.

“We are able to use the optical properties of a cell’s structure to serve as a marker for disease,” said Backman. “These are changes within the tissue than cannot be detected through any other means. Neither antibodies nor diagnostic assays can detect them.”

In the study, the researchers scanned tissue samples from 19 people already diagnosed with pancreatic cancer and 32 without the disease. They correctly distinguished patients with cancer at an accuracy, or sensitivity, of 95%. And according to the NSF, “the clearest results came from patients in the earliest stage of cancer.”

Those markers are also independent of other factors within the tissue, such as whether a patient is a smoker or the location, stage or size of the tumor in the pancreas, Backman said.

Backman emphasized that this was a pilot study and the research team’s finding must still be validated. Toward this goal, the researchers have enrolled 200 patients.

Such a technique, which could be three to five years away from the clinic, would be very important in detecting pancreatic cancer, Backman told MDD, specifically because there are so many problems with the existing methods for diagnosing the deadly disease.

For example, he said, that you “can’t scope the patient, can’t take biopsy from the patient and can’t do a tissue aspiration, because it’s very dangerous.”

And complicated, with a 20% rate of complications and acute pancreatitis. So, he said those procedures should not be pursued “unless you really have a strong reason to believe the patient has pancreatic cancer ... ”

“And if you think the patient has pancreatic cancer, because of a mass found on the whole body imaging, for example, like MRI or CT, or if a patient has symptoms, it’s pretty much by definition [too] late to save the patient,” he said.

Going one step further, the said if a physician can tell the patient has pancreatic cancer, “then these more rigorous and dangerous procedures” are simply not “justifiable,” he said.

Backman called it “a vicious cycle,” and knowing that led to the original hypothesis that perhaps the optical technology could be used for pancreatic cancer, i.e., “to take reading from a tissue, close enough to the pancreas, but from a part of the tissue that is relatively easily accessible and can be done without the risk.”

The researchers have partnered with American BioOptics (Chicago) to fully develop the technology. In July, the company received an NSF Small Business Innovation Research grant to further develop the technology for colon cancer screening and ready the system for commercialization.

In addition to NSF support, the study was also supposed by the National Institutes of Health.