Can a Saliva Test Spot Early Pancreatic Cancer?
Early Research Suggests Bacteria in the Mouth May One Day Help Diagnose Pancreatic Cancer
Early Screening Test for Pancreatic Cancer continued...
The researchers first found differences in the bacteria in the spit of 10 people with pancreatic cancer, which had not yet spread, and 10 people without pancreatic cancer. Next, they analyzed saliva from 28 pancreatic cancer patients and 28 healthy people to verify their findings.
They also compared these findings with those from 27 people who had chronic inflammation of the pancreas, a condition that may increase risk for pancreatic cancer.
Two types of bacteria, Neisseria elongata and Streptococcus mitis, were less common in people with pancreatic cancer. Levels of another bacteria species, Granulicatella adjacens, were significantly higher among people with pancreatic cancer.
Whether these bacteria are causing pancreatic cancer or merely reflecting its presence it is not known, but researchers suspect it is the former.
"We don't have a handle on this yet, but we suspect that the inciting event is the colonization or alteration of bacteria in the mouth," Farrell says.
This isn't the first time that gum disease has been linked to health problems elsewhere in the body. Gum infection causes inflammation in the mouth, and body-wide inflammation is also linked to many diseases including heart disease, stroke, diabetes, and certain cancers.
Test Not Ready for Prime Time
Margaret Tempero, MD, says the new paper is interesting, exciting, and evocative, but a lot more work is needed. She is the director of research programs and deputy director at the UCSF Helen Diller Family Comprehensive Cancer Center in San Francisco.
"Everybody would agree that an early diagnostic test for pancreatic cancer would be the key ingredient to curing more patients," says Tempero, who is also a member of the Pancreatic Cancer Action Network's scientific advisory board. "We know that if we can diagnose pancreatic cancer early and if we have a chance to remove the cancer, we can cure it, so anything that gets us close to that is important."
But -- and it's a big but -- it's not likely there will ever be a simple indicator that says you've got pancreatic cancer.
"Taking a blood test or a swab of saliva and saying we have a test for pancreatic cancer isn't likely to happen," she says.