If you agree to take part in this study, you will have a PET-CT scan performed. The picture produced by this scan will be compared to a standard CT scan to see if any additional tumors can be located. If the study doctor thinks that additional tumors are present, a biopsy may need to be performed to check the status of the tumors. The type of biopsy will depend on where the tumor(s) are located on the body. If a biopsy is performed, you will sign a separate consent.