Integrated PET/CT and cancer imaging.

Integrated Positron Emission Tomography/Computed Tomography (PET/CT) is an imaging technique that was introduced in clinical practice in 1998. PET/CT is the combination of two different examination techniques in one machine: Computed Tomography (CT) giving anatomic information and Positron Emission Tomography (PET) giving metabolic information. PET/CT has two major advantages: CT can be used for attenuation correction and PET/CT improves diagnostic accuracy when compared to CT and PET alone.The quality of PET/CT images depends on different parameters such as CT dose, patient respiration, and the use of intravenous (i.v.) and per oral (PO) contrast. A rapidly expanding amount of literature demonstrates the additional value of PET/CT in the diagnosis, staging, prognosis, treatment planning, assessment of treatment response and diagnosis of recurrence of many tumor types. CT increases the sensitivity of the PET/CT examination, but the most beneficial effect of having the CT data is the increase of the specificity of the PET data. PET data also helps to specify CT information.The utility of PET/CT for tumor staging, which is one of the major imaging study indication, seems to be very high, and therefore PET/CT may become the scanner of the future. Till this moment there are no many published studies about the cost-effectiveness of PET/CT. The integration of PET/CT in clinical practice will result in higher equipment running costs, but these costs are likely not to be prohibitive to the diffusion of this combined technology.