INTRODUCTION: Second-generation tau-PET tracers like [ METHODS: Participants were assigned to exclusive categorical diagnoses based on their amyloid (Aβ) and cognitive status. We quantified mesiotemporal (MTL) and neocortical [ RESULTS: Among the 28 Aβ- impaired subjects, only five presented significant and isolated mesiotemporal signal, most of them being suspected of primary age-related tauopathy (PART). Only two Aβ- impaired patients (7%) presented positive neocortical signal, both being diagnosed with fronto-temporal degeneration (FTD). The Tau-PET results of all the remaining Aβ- patients were comparable to the CU population, including eight other FTD patients. Importantly, 4R-only tauopathies (CBD and PSP) and sv-PPA were negative. CONCLUSION: [