Stopping Rules: The subject is free to withdraw at any time. The investigator also has the right to withdraw a subject from the study in the event of intercurrent illness or other reasons concerning the health or well being of the subject, or in case of lack of cooperation. Should a subject decide to withdraw or the investigator decide to withdraw the subject after administration of FDG, all efforts will be made to complete and report follow-up observations as thoroughly as possible providing consent is still valid. A complete final evaluation at the time of the subject's withdrawal is to be made with an explanation of why the subject is withdrawing or being withdrawn from the study. If the reason for withdrawing a subject from the study is a specific event or an abnormal laboratory test result, the event or test result must be recorded as an adverse event and entered into the Case Report Form.