Even if measuring microRNAs does not turn out to be sensitive enough for general screening, it would arm doctors with a great tool for screening at-risk individuals, Bloomston says. Of course, singling out those groups is half the battle in a disease such as pancreatic cancer. Those with a family history, which accounts for about 10 percent of pancreatic cancers, would make up one obvious group. Sen and his colleagues are currently studying gene mutations that could play a part in pancreatic malignancies, and also provide a preliminary tool to identify more susceptible individuals. Researchers have also linked drinking and smoking to this form of cancer, so people who partake in these activities might also qualify for microRNA screening.
Pancreatic cancer is the third type of cancer, after prostate and ovarian, to be associated with altered levels of microRNAs in the blood. A blood test for microRNA levels could screen patients at risk for more than one type of cancer or, as scientists gain better knowledge of tissue-specific microRNAs, specific cancers. And, one day, screening may not even involve a needle if, as Bloomston points out, scientists can confirm levels in urine and saliva.