Clinical and pathology characteristics of colorectal polyps in Iranian population.

Background and Aim: Colon polyps are important lesions and a concern because of the potential for colorectal cancer, one of the most common causes of cancer-related deaths in Iran. The distribution of polyps in the colon may affect the efficacy of screening modalities. The aim of this study was to determine clinical and pathology characteristics of colorectal polyps in the Iranian population.
Methods: This cross sectional survey covered 856 polypectomies in 716 patients, with anatomical distribution, size and histopathology of the polyps described in 2004-2009 in the educational hospital of Taleghani in Tehran.
Results: Polyps were observed in 437 males and 279 females. The distribution was 3.12 percent located in the rectum, 19.6 percent in the sigmoid colon, 24.4 percent in the descending colon, 13.9 percent in the transverse colon, and 29.6 percent in the cecum and ascending colon. Some 77(9%) were non-neoplastic and 779 (91%) were neoplastic. Adenomas were present in 727 (85%) cases, of these 411 (56%) were left-sided and 316 (44% ) were right-sided. Carcinoma was observed in 52 cases, 18(34.5%) being left sided and 34(65.5% of carcinomas) right sided. Of the total, 354 were advance polyp (>1cm, villous type, high grade dysplasia), 87(34%) being found in patients under 50 years of age and 149 (58.6 %) being right sided.
Conclusion: This study showed a significant number of adenomas and carcinomas to lie proximal to the splenic flexure. Thus, it is expected that examination of the colon limited to the splenic flexure would miss 44% of such lesions. The increasing right-sided prevalence of these lesions with age suggests that evaluation of the proximal bowel is particularly important in older people. In addition there were higher stages of dysplasia and malignancy in larger polyps.