KRT5 and neoplasm: Hence, to study compartment-related tumor cell phenotypes, we used multiplex IHC with a panel of six markers, two classical (caudal type homeobox 2 [CDX2], mucin 5AC oligomeric mucus/gel forming [MUC5AC]), and four basal markers (Keratin [KRT]5, high mobility group AT-hook 2 [HMGA2], Carbohydrate antigen [CA]125/MUC16, and KRT17; Fig. 2a) in a subcohort of n = 31 patients, for which extensive IHC was available and lobular invasion was present at different degrees (clinical characteristics in Table 1, flow chart of sample analysis in Supplementary Fig. 1).