Pancreatic ductal adenocarcinoma, the most common type of cancer of the pancreas, is also the most lethal of all cancers, with a mortality rate that is approximately the same as the rate of incidence. The American Cancer Society reports that more than 42,000 people in the United States were diagnosed with pancreatic cancer in 2009, and more than 35,000 people died from the disease. Pancreatic cancer is the fourth leading cause of cancer death in the United States. Typical symptoms of abdominal pain and jaundice occur in the advanced stage of the disease, making it difficult to fight. Fewer than 5% of those diagnosed with the disease live for 5 years, and full remission is very rare. A reliable method of early diagnosis is needed.
In recent years, technological advances have pushed the concept of salivary diagnostics for systemic disease to the forefront of scientific attention. The UCLA researchers successfully linked changes in the molecular signatures found in human saliva to the presence of early-stage pancreatic cancer in this study. The researchers identified 4 important messenger RNA (mRNA) biomarkers: KRAS, MBD3L2, ACRV1, and DPM1. These biomarkers differentiate pancreatic cancer patients from noncancer subjects (both those diagnosed with chronic pancreatitis and healthy controls) with 90% sensitivity and 95% specificity. Saliva-based diagnostic methods for pancreatic cancer are simple and noninvasive, and may also represent an improvement in specificity and sensitivity over currently used procedures such as blood tests for early detection of pancreatic cancer. Due to the study’s modest sample size of 90 human subjects, the researchers acknowledge limitations yet express enthusiasm for further research. They are formulating plans to test the salivary biomarkers in a larger population in a multicenter study. They also note that the potential for salivary mRNA biomarkers to identify very early-stage and even pre-invasive pancreatic cancer requires further investigation.
(Source: ScienceDaily, February 17, 2010)