Correspondence between flat aberrant crypt foci and mucin-depleted foci in rodent colon carcinogenesis.

BACKGROUND Flat aberrant crypt foci (flat ACF) and mucin-depleted foci (MDF) are preneoplastic lesions identified in the colon of carcinogen-treated rodents stained with methylene blue (MB) and high iron diamine-alcian blue (HID-AB), respectively. The correspondence between flat ACF and MDF in the same colon of Min mice treated with azoxymethane (AOM) and of F344 rats treated with 1,2-dimethylhydrazine (DMH) was explored. MATERIALS AND METHODS The position of each flat ACF was recorded on a digitally constructed photographic map of the MB-stained colon. The same colons were then stained with HID-AB and the position of each MDF was compared with that of flat ACF. RESULTS The fraction of coincident lesions, identified as both flat ACF and MDF with the two staining methods, was 57% and 42%, in the Min mice and F344 rats, respectively. Flat ACF or MDF not coincident with the two staining methods were either undetectable or ACF with one of the two methods. CONCLUSION Flat ACF and MDF show considerable, but not total, overlap.