"With just a drop of blood doctors may one day be able to detect pancreatic cancer in its early stages before it has become deadly a new study suggests. An international team of researchers was able to identify  percent of patients with latestage pancreatic cancer as well as those with earlier stage disease by looking for a protein in the blood that is made in abundance by tumor cells. That protein turns up in tiny virussized particles called exosomes which are excreted by all of the bodys cells according to the study published in Nature. But by good fortune the protein turns up in exosomes only when there is cancer so its presence could be an early and testable marker for the disease. Its rare to discover pancreatic cancer early said study coauthor Dr. Raghu Kalluri professor and chairman of the department of cancer biology at the MD Anderson Cancer Center. People dont feel any symptoms that make them want to go to the clinic until their cancer is stage  or stage  he added. Using this test we were  percent accurate at identifying all cancer patients. In   Americans will be diagnosed with pancreatic cancer according to estimates by the National Cancer Institute. And an estimated  will die from the disease. It is the most deadly cancer with just . percent surviving five years. For perspective over the course of a lifetime . percent of Americans will develop pancreatic cancer. While quite promising the new findings will need to be verified and validated by other studies experts told NBC News. And even if it passes muster it will take some time before a test could be developed to screen for the disease. Kalluri and his colleagues examined serum samples from  patients with pancreatic cancer  patients with breast cancer and  healthy volunteers. They found levels of the protein in exosomes correlated with the severity of the disease  so there was more in patients with more advanced disease. It was not present in the healthy volunteers. Even more promising are the findings from the seven patients with early pancreatic cancer that were detectable through their protein levels. Further levels dropped when patients had surgery to remove their tumors so the marker could also be used to follow the progression of the disease Kalluri said. Kalluri says that a screening test might be available in as little as a year. But he said this is just a speculation based on the current strength of the study."