Blood Sample To Detect Cancer (IMAGE) Umea University Caption With the use of a blood sample equivalent to one drop of blood, a new RNA test of blood platelets can be used to detect cancer. Credit Wikipedia Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.