NAPSA and Alzheimer disease: ST6GALNAC1 showed higher sensitivity and accuracy than the existing IHC markers for AD, such as TTF-1 and napsin A. In contrast, SPATS2 showed a unique staining pattern, where it was positive in SCC cases, even when the staining results of the existing SCC markers (p40, DSG3, CK5 and CK6) were negative (Fig. 4b, Additional file 1: Table S2).