Colorectal Neoplasms in Symptomatic Patients without Evidence of Bleeding: A Prospective Study in an Iranian Population

Background: Colorectal cancer (CRC) is a preventable disease with a high mortality and morbidity. Data onits prevalence are lacking in Iran, as well as for adenomatous polyps. This study was conducted to estimateprevalence of CRC in patients with long lasting colonic symptoms (except for known risk factors for cancer andthose with rectal bleeding) who underwent total colonoscopy.
Methods: This prospective study was carried outin Imam Hospital, Tabriz University of Medical Sciences, Iran. The recruitment procedure involved 228individuals aged more than 30 who visited a gastroenterologist because of lower gastrointestinal tract symptomsand had criteria for a colonoscopy. The endoscopist visualized the caecum in all, documented by a photo ofcaecum and/or specimen of the terminal ileum. The Chi square test and multiple logistic regression analysiswere used to determine the significance of associations between different symptoms and colonoscopic findings.
Results: Thirty four subjects (14.9%) were found to have colorectal neoplasia and 112 (49.1%) had a completelynormal colon. Adenomatous polyps were detected in 27 patients, which included 15.6% of men and 7.0% ofwomen. Most of them were tubular (58.3%) and severe dysplasia was reported in only 3 cases (11.1%). Meanage of patients with a polyp (51.1±12.5 years) was not significantly different compared to others (p=0.381) normean duration of symptoms (21.1 months, p=0.435). Cancer was detected in 7 (3.1%) of our study population,the mean age of 65.7±6.0 years in this case being significantly elevated (p<0.0005). None of the symptoms werepredictors of cancer or polyps. This result was the same by a multivariate analysis including age, gender andduration of the symptoms.
Conclusion: The low prevalence of colorectal neoplasms as well as the less advancedpattern of adenomas in Iran are compatible with other data from Asia and the Middle East, contrasting withwestern countries.