PPIB and primary progressive aphasia: When referring to post-2007 studies reporting post-mortem data according to current TDP-43 classification systems (Mackenzie et al., 2011), the most common histological finding, regardless of PPA variants, was TDP-43-B (≈50% of cases), in line with this subtype being the pathological substrate of ALS-FTD/FTD-MND phenotypes (Mackenzie et al., 2011).