Dossier n. 157/2007 [Abstract] FDG-PET in oncology. Criteria for its appropriate use

Positron Emission Tomography is an important diagnostic technology which allows non-invasive imaging through the study of metabolic processes and their alterations caused by a number of diseases. Numerous technology assessment reports have evaluated the quality and relevance of published clinical trials in order to define FDG-PET’s effectiveness in oncology. This report is the update of a previous document produced by the Agenzia sanitaria regionale of Emilia-Romagna, Italy in 2002, on criteria for the appropriate use of FDG-PET.

The report has been developed according to the following steps.

Institution of a multidisciplinary regional panel

The composition of the multidisciplinary panel is as follows: 7 nuclear physicians, 6 oncologists, 3 internal medicine physicians, 2 pneumologists, 1 emathologist, 2 health trust directors and 3 methodologists.

Systematic research and critical appraisal of the scientific literature

The systematic research for the primary studies (studies on effectiveness and change in management), for systematic reviews and metanalysis and for guidelines and HTA reports was carried out on main databases (MEDLINE, EMBASE, CINAHL e database of the Centre for Reviews and Dissemination). Tables of evidence have been produced describing methodological characteristics of the studies and main results.

Research questions and clinical scenarios

The list of research questions to be discussed by the panellists was compiled drawing from the scenarios reported in the 2002 document, integrated by the clinical cases collected during the 2002 Audit and by the suggestions made by the panellists. The total number of clinical scenarios discussed by the panel were 66.

Criteria of appropriateness

The panel discussed and agreed the following definitions for the classification of levels of appropriateness for the use of FDG-PET in oncology.

Appropriate
When the results from the available studies fulfil all the following:

• there is evidence of a  higher diagnostic performance (higher sensitivity and specificity) for FDG-PET compared with other current techniques;
• the information obtained from FDG-PET has an influence on clinical practice
• this information has a plausible impact on the patient’s outcome as it allows the adoption of effective practice or the non adoption of ineffective or harmful practice.

Potentially useful
Results from available studies show that FDG-PET has a better diagnostic performance (higher sensitivity and specificity) than other current techniques but they do not provide evidence on the impact on clinical practice and patients’ outcome.

Of unproven usefulness
Results from at least two independent and rigorous studies on the test performance are not yet available, although there is a clinical rationale for a useful application of FDG-PET.

Indeterminate due to lack of published research
Clinical scenarios for which studies on use of FDG-PET are lacking.

Inappropriate
When the clinical situation and the stage of the disease is such that no further diagnostic information could modify the therapeutic approach, or where results from available studies show a worse performance for FDG-PET compared to current techniques.

Panel’s evaluation of clinical scenarios

All panellists voted each clinical scenario using the modified RAND method and applying their score on a ordinal scale going from 1 to 9 (1 = definitely appropriate; 9 = definitely inappropriate).

The criteria reported in this document are to be intended as guidance for programmes of clinical governance aimed at

• advising on the use of FDG-PET in oncology;
• analysing a posteriori appropriate use;
• contributing to the assessment of demand for the technology and to the planning of the regional health service.

They are not to be considered as guidelines or recommendations for the single patient and they do not imply that FDG-PET should be carried out in all patients whose characteristics correspond to those of the clinical scenarios. It is up to the clinician in charge to evaluate the test’s appropriateness  on the basis of the foreseen possible contribution to clinical decision-making. The four levels of appropriateness (1. appropriate; 2. potentially useful; 3. of unproven usefulness; 4. inappropriate) set the contexts within which the utility of FDG-PET can most likely be considered high, intermediate or absent for patients’ care.

The working group has committed itself to annually assess the need to update this document.