Aim: The aim of this study was to report the anatomical location and histologic type of colorectal polyps in a large series of Iranian patients that attended for colonoscopy.
Background: Polyps that develop through the adenoma-carcinoma pathway are considered neoplastic and may eventually progress to invasive carcinomas. In addition polyps can develop with no neoplastic potential. These neoplastic and non-neoplastic polyps can be identified and removed at colonoscopy.
Patients and methods: In this retrospective study, the medical records of patients who had attended for colonoscopy were reviewed. Patient demographics and colonoscopy findings were reviewed. The anatomical location, macroscopic appearance and histological assessment of any polyps were recorded.
Results: 716 patients' records were reviewed. 437 patients (61 %) were male and 279(39%) were females. The mean patient age was 55.3 yr (18-89 yr). A total of 936 polyps were identified. 779 (83.3%) were neoplastic and 157(16.7%) polyps were non-neoplastic.727 of the polyps were adenomatous. Of the 727 adenomatous polyps: 198(27.2%) were in sigmoid, 156(21.24%) were in caecum and ascending colon, 153(21%) were in descending colon, 131(18%) were in transverse colon and 89(12.3%) were in rectum. 39.5% of adenomas were proximal to the splenic flexure. Carcinoma was observed in 52 cases. 18 carcinomas (34.5%) were left sided and 34 (65.5% of carcinomas) were right sided. Of the 716 patients, 179 patients (25%) had synchronous lesion(s).
Conclusion: A significant number of adenomas and carcinomas lie proximal to the splenic flexure and occur in the absence of distal lesions. These lesions would be missed if the distal colon was examined and the entire colon examined only if a distal lesion was identified.
Keywords: Colonoscopy; Colorectal cancer; Screening.