Mise au point : TEP-choline et cancer de la prostate

Abstract

PET with (18)F-Fluorocholine has authorization for the diagnosis of bone metastases. There are no limitations to the realization of this exam but androgen deprivation treatment should not be initiated or modified before performing TEP-choline. Some studies have shown a good correlation between choline uptake within the prostate and the tumor, if the size is greater than 5 mm; this exam is interesting in case of negative biopsy. In the initial staging of high-risk prostate cancer, metastatic nodes could be detected if there are more than 5 mm, especially those localized outside the lymphadenectomy area. TEP-choline is the most efficient exam that could detect intra-medullary bone metastases. It could realize the staging N and M in one procedure, and it could replace conventional imaging exams to detect lesions at an early stage. In the evaluation of recurrent disease, TEP-choline is able to detect the site of relapse--local, pelvic nodal or bone metastases--from a threshold of 1 ng/mL, less if the velocity value is greater than 1 ng/mL per year or the doubling time less than 6 months. For low PSA value, (around 5 ng/mL), relapse is usually isolated, either be local or nodal or metastatic. TEP-choline could be carried out in a first intention to consider a local salvage treatment. Bladder accumulation of choline can hide local small volume recurrence: overcome this drawback by the administration of Furosemide. In case of high-level PSA, Standard examinations (scintigraphy, CT…) are sufficient to detect the site of relapse.