Blood tests that detect potential tumor growth show promise for early cancer treatment.
Blood tests that could detect cancer before it develops show promise for the future of screening and prevention, though researchers continue to test which cancer clues are good markers for diagnosis. A review article in the journal Clinical Cancer Research by investigators from Baylor Scott & White Research Institute examines the potential for microRNAs – molecules that regulate gene expression – to detect gastrointestinal cancer in blood and other bodily fluids, known as a liquid biopsy.

"A significant number of patients still develop late–stage gastrointestinal cancer, when treatment options are limited," said Ajay Goel, PhD, director of gastrointestinal research and translational genomics and oncology at Baylor Scott & White Research Institute and one of the lead authors of the article. "Liquid biopsies hold promise for detecting cancer before a tumor or symptoms even develop and may prevent some patients from undergoing invasive surgical and needle biopsies."

As cancer tumors grow, they shed tiny DNA particles into the bloodstream. Liquid biopsies would detect these particles, helping doctors diagnose the specific type of cancer before it is found by traditional screenings like a CT scan, mammogram or colonoscopy. Clinicians hope making cancer detection easier for patients will lead to more people being screened and more lives saved.

Researchers testing liquid biopsies have found microRNAs emerging as potential biomarkers due to their small size and stability in a variety of bodily fluids. Dr. Goel and his team reviewed studies in colorectal cancer, esophageal cancer, gastric cancer, pancreatic cancer, and hepatocellular and biliary cancer that show microRNAs may play a key role in future development of the approach.

"Continued research into microRNAs as a biomarkers in this approach will likely usher in a new era of personalized medicine for cancer patients," Dr. Goel said. "That may be 20, 30 or 50 years down the road, but that's the hope."