Fig. 1.

Topographic views of (A) ACF, (B) BCAC, and (C) MDF. (A) Note that three identical crypts are seen in one focus (methylene blue staining). (B) Crypts with accumulations of β-catenin protein in cytoplasm are present (immunohistochemical staining). (C) A focal lesion characterized by the absence or very small production of mucin (seen as very thin blue-stained crypts) is present (high-iron diamine-Alcian blue staining). ACF, aberrant crypt foci; BCAC, β-catenin accumulated crypts; MDF, mucin-depleted foci.