A multicenter study of @entity2513 . Rationale, objectives, methods and characteristics of the study cohort. The Multicentric Study of @entity2513 ( XXXX ) Workgroup.

@entity1 @entity17205 @entity1127 @entity1412 @entity29 @entity14 @entity3 @entity652 @entity420 @entity2513
BACKGROUND AND AIMS: The Multicenter Study of @entity2513 ( @entity17205 ) is a retrospective-prospective cohort study involving four Gastrointestinal Endoscopy Units in Italy. The main aim of the study is to evaluate the relationship between clinical and pathologic information at index colonoscopy and subsequent incidence of @entity652 and @entity14 . We report the rationale, objectives and methods of the study, including @entity1 characteristics at initial presentation. METHODS: All @entity1 were consecutively identified from the endoscopy registries of the four Centres from January 1, 1985 to December 31, 1992. Inclusion criteria were: age 18-69 years, endoscopy performed with adequate toilette at least up to the rectosigmoid junction, and removal of all detectable @entity1127 . Exclusion criteria were: @entity1412 , @entity29 , @entity420 in @entity652 with infiltrated margins, previous @entity3 at any site, colon resection and geographic inaccessibility. RESULTS: Out of 20,071 @entity1 who underwent endoscopy at the four Centres, 11,959 fulfilled the eligibility criteria (5,892 males and 6,067 females, mean age = 51.1 +/- 11.6 years). The main reasons for exclusion were age (n = 4,020) and previous or present @entity14 (n = 2,389). Symptoms were the most common reason for referral (72.3%), while post-polypectomy follow-up and positive fecal occult blood accounted for most of the remaining cases. A pancolonoscopy was performed in 3,088 @entity1 (25.8%), while a left-sided endoscopy was performed in 7,887 (66%). A total number of 4,810 @entity1127 were removed from 2,699 @entity1 (2,994 @entity652 , 1,580 @entity1127 and 236 @entity1127 lost after resection). A significant association (p < 0.001) between age and the endoscopic findings was observed. The subjects without @entity1127 (n = 9,198) had the lowest age (mean = 49.9; 95%CL = 49.6-50.1) followed by the @entity1 with @entity1127 (n = 661; mean age = 52.3; 95%CL = 51.5-53.1), and the @entity1 with @entity652 (n = 1,732; mean age = 56.2; 95%CL = 55.8-56.6), and the @entity1 with @entity1127 and @entity652 (n = 306; mean age = 57.2; 95%CL = 56.3-58.2). @entity1127 were diagnosed more frequently in males than in females (28.6% versus 17.0%; p < 0.0001). CONCLUSION: This study provides some insights in the natural history of @entity14 and stresses the need to develop adequate strategies in the follow-up of subjects after either positive or negative colonoscopy.
