Crypts With Corrupted Shapes in Non-polypoid Adenomas

Colonic crypts with normal epithelial lining exhibiting corrupted shapes (NECS) have been previously found beneath the adenomatous tissue of polypoid conventional adenomas, in both rats and humans.

To assess the frequency of NECS in non-polypoid colonic flat adenomas (FAs) and lateral-spreading adenomas (LSAs).

Histological hematoxylin and eosin-stained sections from 51 non-polypoid colonic adenomas were scrutinized over a 10-mm field of vision (FOV). FAs were regarded lesions encompassed within the FOV and LSAs as those surpassing that limit. The NECS/mm ratio was calculated in individual lesions as the number of NECS beneath the adenomatous tissue, divided by the length (mm) of the FA and LSA.

Out of the 51 non-polypoid adenomas, 27 were FAs and the remaining 24 LSAs. All 51 non-polypoid lesions were tubular adenomas. The mean number of NECS in FAs was 6.29 (range=2-10) and in LSAs was 15.29 (range=7-41) (p<0.05). On the other hand, the mean NECS/mm ratio in FAs was 0.94 (range=0.50-2.00) and in LSAs was 0.92 (range=0.40-2.93). Thus, no essential differences in the number of NECS/mm was found between FA and LSA.

The accretion of NECS below the neoplastic canopy of FA and LSA contrasts with the rare occurrence of NECS in normal colonic mucosa. This finding emerges as a previously unaddressed major event, an event that might play an important role in the histogenesis of non-polypoid adenomas of the colon.