We would like to demonstrate that diagnosis performance of PET/CT scan without and with contrast agent (COMBI TEP), are equivalent or better than those of PET/ non enhanced CT scan (PET scan) associated with an enhanced CT scan. This research project is a pilot study given the few available data concerning this imaging exam reproducibility. This study allows us to assess the feasibility of such a large-scale study, but also to evaluate COMBI TEP performance. From these estimates, we can then consider a comparative study to evaluate the performance of COMBI PET.