The University Clinic of Navarra has successfully applied, for the first time in Spain, PET-OTA equipment together with the drug 18F -DOPA to detect neuroendocrine tumors that are difficult to diagnose. PET-OTA combines two diagnostic procedures: Positron Emission Tomography (PET) and Computer-Axial Tomography (CT). A common feature to neuroendocrine tumors is that they are able to detect and metabolize the amino acid L-DOPA. The 18F-DOPA radiopharmaceutical is analogous to the L-DOPA marked with FLUOR-18 and emits positrons so the tumors marked with it can be detected with the PET-OTA equipment. This diagnostic technique is common in the study of Parkinson's disease.