[Serrated lesions of the large intestine: Prevalence analysis and clinical and morphologic characteristics].

Objective: to retrospectively estimate the prevalence of serrated lesions of the large intestine and to reveal the features of dis- tribution of serrated lesions in the previously diagnosed classical adenomas and hyperplastic polyps.

Material And Methods: A continuous sampling method was used to take biopsy specimens from the archive material of 440 polypoid lesions of the large intestine, which had entered in 2012-2013, and which were be morphologically reexamined by three experts. The mor- phological criteria for diagnosing different types of serrated lesions were taken according to the 2010 WHO classification of premalignant lesions of the large intestine and to the recommendations from an expert panel (Am J of Gastroenterology 2012).

[Serrated lesions of the large bowel].

The 2010 WHO classification identifies a new group of pretumor lesions of the large bowel--serrated masses, which includes hyperplastic polyps (HPs), sessile serrated adenomas/polyps (SSA/P), and traditional serrated adenomas (TSA). Serrated masses are a heterogeneous group characterized by serrated gland lumens and, in most cases, without dysplasia. An enlarged proliferative zone, elongated crypts, and no cytological atypia in addition to a serrated lumen are typical of HPs.

[The alternative way of colorectal cancer developing. The histogenetic and molecular features of serrated lesions (review, continued)].

The occurrence of colorectal cancer can be traced in two ways: from conventional adenomas with the APC-gene mutation (model Fearon-Vogelstein) and the "serrated way", that has a unique genetic profile and morphological characteristics at the early stages. These neoplasms are determined from 7 to 9%. The risk of developing cancer of them is 7.

[Polyposis of the stomach. Endoscopic treatment or follow-up?].

Out of 3243 patients with gastric polips, polyposis was diagnosed in 298 ones including 135 cases of complicated and 163 cases of uncomplicated forms. Hyperplastic polips were diagnosed in 281 patients. Along with hyperplastic polyps, solitary adenomas were diagnosed in 9 cases, Peitz-Jegerc polyps - in 6, and juvenile polyps - in 2.