Although pancreatic cancer is the 10th most common cancer in the US, it is the fourth most common cause of cancer deaths, because 9 in 10 cases are only diagnosed after the cancer has spread and there is no effective treatment. Now, a promising pilot study that tested an endoscope with an oxygen sensor raises hope that the deadly disease may be detected earlier via a simple procedure.
Writing in the journal Gastrointestinal Endoscopy, researchers from the Mayo Clinic in Florida describe how they tested the ability of the device to recognize pancreatic cancer.
In two small groups of patients – 14 patients already diagnosed with the disease, and another 10 who were disease-free – the device showed a sensitivity of 92% and a specificity of 86% in detecting pancreatic cancer.
This suggests the procedure would find 92% of patients with the disease and would rule out 86% of patients without the disease.
The device is an endoscope – a thin, long, flexible tube with a light and a camera – that also has a blood oxygen sensor attached to it, like the fingerclip sensor used to measure blood oxygen in patients.
The device measures changes in blood flow in the tissues near the pancreas. It works on the idea that tumors alter blood flow in surrounding tissue as they demand more oxygen to fuel their growth.
To take a measurement, the endoscope is passed into the stomach and duodenum, which is right next to the pancreas.
Senior investigator and gastroenterologist Michael Wallace, a professor of Medicine at the Mayo Clinic, says the only way to accurately test pancreatic cancer at an early stage is to remove some of the organ, and adds: “We need new ways to detect pancreatic cancer effectively, and simply, as early as possible.”
He says although theirs is just a small pilot study, “the outcome is very promising,” and they are confident they can confirm the results in a much larger study in patients in the US and Europe.
He notes their method is quite different to how cancer is normally detected – primarily because they are not trying to sense changes in the tumor but in nearby tissue that appears normal.
“It relies on a principle now being increasingly acknowledged, called a cancer field effect,” he explains. “Instead of looking for the needle in the haystack, we now look at the haystack to see how it is different when there’s a needle inside.”
Prof. Wallace explains their findings in the video below:
The team is also testing the effectiveness of the device in detecting esophageal and colon cancers.
The National Institutes of Health and National Cancer Institute, plus the Mayo Clinic Foundation for Medical Education and Research helped fund the study.
In March 2013, Medical News Today reported how researchers in Japan are also developing a new, faster way to diagnose pancreatic cancer early using metabolomic analysis. When they validated the method, it showed a sensitivity of 71.4% and a specificity of 78.1%.