This study is the first time that a new experimental drug called [18F]-SKI-249380 is being used in people. [18F]-SKI-249380 is not a therapeutic drug. [18F]-SKI-249380 is a drug that will be used with PET scanners to 'see' where [18F]-SKI-249380 goes in the body, after its injected. The researchers believe that scans with [18F]-SKI-249380 might be able to find tumors in patients.