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Researchers in Japan have developed a new blood test that may hold promise for catching pancreatic cancer early enough to improve patient survival. That could be good news for diabetes patients, who may be at an increased risk of developing pancreatic cancer if they take certain medications, including Januvia and Byetta.

The new screening method involves metabolomics, an emerging field of science centered on small molecules called metabolites. These byproducts of metabolism, found in the blood, can be measured and analyzed to identify patients with pancreatic and other forms of cancer.

Pancreatic cancer is the fourth leading cause of cancer-related death in the United States. Survival is poor compared with other cancers because most patients are diagnosed at an advanced stage, when the cancer is too far spread to be cured with surgery.

“This novel diagnostic approach, which is safe and easy to apply as a screening method, is expected to improve the prognosis of patients with pancreatic cancer by detecting their cancers early, when still in a resectable and curable state,” said lead researcher Dr. Masaru Yoshida, associate professor and chief of the Division of Metabolomics Research at Kobe University Graduate School of Medicine in Kobe, Japan.

Yoshida and his colleagues describe their findings in a study published online March 29 in the journal Cancer Epidemiology, Biomarkers & Prevention.

Detecting a ‘Silent Disease’

With fewer than 5 percent of patients surviving longer than five years after diagnosis, pancreatic cancer is one of the deadliest forms of cancer. Because early pancreatic cancer usually has no warning signs or symptoms, it is often called a silent disease.

The pancreas is a 6-inch long glandular organ that secretes enzymes to aid in food digestion. It also makes several important hormones, including insulin, which controls the levels of sugar in the blood.

Because the pancreas is located behind the stomach deep within in the abdomen, it’s difficult for doctors to see or feel early-stage tumors during physical exams. According to Yoshida, distant spread at the time of detection makes more than 80 percent of pancreatic cancers inoperable.

These problems highlight a critical need for early detection, but current screening methods for the disease fall short. Imaging scans like ultrasounds and CT scans are too costly to be used practically for screening. Doctors can use other blood tests to detect the cancer, such as the CA19-9 blood test, but this method is neither unique to pancreatic cancer nor efficient at identifying the disease at an early stage.

Success with Metabolomics

In their search for a more viable screening method, Yoshida and his team evaluated the usefulness of metabolomics analysis. Using a technique known as gas chromatography-mass spectrometry, the researchers analyzed blood samples to pinpoint metabolites that are expressed in patients with pancreatic cancer but not healthy patients.

The study used blood samples taken from pancreatic cancer patients, patients with chronic pancreatitis (an inflamed pancreas) and healthy volunteers.

Researchers randomly assigned 43 patients with pancreatic cancer and 42 healthy volunteers to what they called a training set to reach their initial findings. To validate the findings, they repeated the test with a second set comprised of 42 patients with pancreatic cancer, 23 chronic pancreatitis patients and 41 healthy people.

After analyzing the metabolomics data, Yoshida’s team was able to isolate 18 metabolites that are significantly different in pancreatic cancer patients compared with the healthy patients. The researchers then refined their technique so they could predict a pancreatic cancer diagnosis by measuring the levels of only four metabolites.

“Our diagnostic approach using serum metabolomics possessed higher accuracy than conventional tumor markers, especially at detecting the patients with pancreatic cancer in the cohort that included the patients with chronic pancreatitis,” said Yoshida.

Because Yoshida’s study involved a small sample of patients, his team’s findings must be reproduced in a large-scale clinical trial involving multiple cancer facilities. Only then can the true survival benefit of early detection with metabolomic analysis be confirmed.

Pancreatic Cancer on the Rise

The need for effective and reliable early screening methods is stronger than ever, as rates of pancreatic cancer have been slowly increasing over the last decade. According to the American Cancer Society, more than 45,000 Americans will be diagnosed with pancreatic cancer in 2013.

While studies have shown that certain known risk factors like family history, obesity, smoking and diabetes can increase a person’s likelihood of developing pancreatic cancer, there is growing concern that use of a popular class of diabetes medications may also be linked to the disease.

The U.S. Food and Drug Administration (FDA) is currently investigating new unpublished findings from a group of academic researchers who suggest certain diabetes drugs, such as Januvia and Byetta, are linked to an increased risk of pancreatitis and pre-cancerous changes in the pancreas.

The FDA issued a safety alert in March 2013 explaining that the agency is reviewing the findings to further evaluate the health risks of this class of diabetes medications. Meanwhile, several people who developed pancreatic diseases after taking these drugs have filed lawsuits against the drugs’ manufacturers for failing to disclose the potential health risks.

The FDA has yet to reach any conclusions about the new findings, but will communicate its final decision once the review is complete or additional information becomes available.