[Positron emission tomography in tumor pathology]

After a brief reminder concerning the PET technique and use of FDG, the author sets out to summarize the results of numerous PET centers in the world and in more detail, results of European units he visited. Leaving neurology and cardiology out, the most important works are dealing with tumoral pathology. The sensitivity of the technique is high for localizing tumoral tissue, evaluating lymphatic spread and detecting metastases. On the contrary, specificity is low as non tumoral lesions, especially inflammatory lesions, tuberculosis may pick up FDG though with less intensity. PET contributes to precise staging TNM of cancer, especially in case of pulmonary neoplasms. Results of clinical evaluation of bronchial carcinoma are presented. Other research programs show similar positive results for the staging of digestive tract neoplasm, primary or metastatic lymph node diseases, metastases from a quiescent, unknown primary tumor. The fact that the number of PET units is small explains the relatively poor dissemination of the method. It is rather obvious that the limitation of the number of PET units is due to economic reasons. Since 1990, many scientific evaluations of this technique conclude positively on PET's future. As it essentially is a functional method, the future developments of PET will largely depend on the discovery of new tracers.