OBJECTIVETo explore the endoscopic and histopathological morphology of large intestinal serrated adenomas (SA).

METHODSThe endoscopic and pathological data of 71 SA patients, diagnosed in the Digestive Endoscopy Center, Nanfang Hospital from January 2002 to July 2005, were analyzed retrospectively.

RESULTSForty-seven of the 71 serrated adenomas were protruded (sessile 23, semipedunculated 5, pedunculated 23) and 24 were superficial (flat 16, laterally spreading 8). The mean sizes of the protruded and superficial SA were 10.5 mm and 16.6 mm, respectively, and both of them were frequently located in the sigmoid and rectum. Histopathologically, SA contained tubular glands in 53, tubulovillous glands in 9 and villous glands in 9 cases. Mild dysplasia was found in 47 SAs, moderate dysplasia in 22 SAs, and canceration foci in 2 SAs. The dysplasia of SAs (<10 mm) was significantly better than that of SAs (>or= 10 mm) (P< 0.01). Most IV and III L pit SAs presented villous glands (64%) and tubular glands (68%), respectively. 40% of hyperplastic polyps-like SAs, composed of tubular glands,showed II pit pattern. Atypia in II pit SAs was similar to that in IIIL pit SAs, but was worse than that in IV pit SAs.

CONCLUSIONPolyps with II pit pattern possibly are SAs sometimes. SA with the common characters of neoplastic polyps,should be regarded as a new potential precancerous lesion.