Imaging Techniques in CT: Technical Development

* INCLUSION CRITERIA: * For new or healthy volunteers currently participating in an NIH trial: no CT scan in the last year OR For patients enrolled in a treatment or interventional trial at the NIH: no CT scan in the last 6 months * Lab Eligibility parameters: * For CT and MRI contrast enhanced scans: ---eGFR greater than or equal to 60 mL/min/1.73m(2) within 7 days prior to scanning * For female participants ages 45-60 within 3 days prior to scan (unless post-menopausal or no longer able to bear children, note exemption on initial visit): * Pregnancy test result(blood or urine): Negative * Willing to travel to the NIH for follow-up visits. * Greater than or equal to 45 years old * Able to understand and sign informed consent * Stable clinical status * Volunteer indicates no history of participation in NIH protocols using research radiation in the last 12 months (e.g. PET research scans, NCI Molecular Imaging Center PET scans, etc) EXCLUSION CRITERIA: * Prior CT scan in the last 12 months for new volunteers or healthy volunteers enrolled in NIH trials OR Prior CT scan in the last 6 months for patients enrolled in a treatment or interventional trial * Pregnant women * Over 500 lbs and/or a body circumference that prevents the study subject from lying flat in the scanner * Claustrophobia requiring sedation or anesthesia. * Known or suspected genetic predisposition to cancer * Any contraindications that the research team identifies from the subject, radiology department CT and/or MRI questionnaires, and/or History and Assessment. Exclusion for participation for iodinated contrast for CT (Inclusive of the above exclusion criteria): * Allergy to iodinated contrast for scans (study subject will be eligible for non-contrast scans) * Acute renal failure, renal transplant, dialysis and renal failure (clinically diagnosed).\<TAB\> * Lactating women * Patient preference to not undergo intravenous line placement and/or receive iodinated contrast. Contrast administration is optional and participants may still undergo a non-contrast study. * Use of metformin-containing products less than 24 hours prior To CT contrast administration * Other contraindications to iodinated contrast media as determined by the research team. Exclusion for participation for Gadolinium contrast for MRI (Inclusive of the above exclusion criteria): * Allergy to gadolinium for scans using contrast; will be eligible for non-contrast scans. * Acute renal failure, renal transplant, dialysis and renal failure individuals ( Lab Eligibility parameters and/or clinically diagnosed).\<TAB\> * Lactating women * Patient preference to not undergo intravenous line placement and/or receive gadolinium contrast. Contrast administration is optional and participants may still undergo a non-contrast study. * Other contraindications to gadolinium contrast media as determined by the research team.