Background & aims: A gradual shift of colorectal adenoma and carcinoma location toward the proximal colon has been recently observed both in the United States and Europe. We aimed to study the polyp and adenoma detection rate in a major endoscopy center of northwestern Romania over a 16-year period, and to characterize the distribution and the pathological features of the removed polyps according to age and sex, in order to assess the trend of proximal adenoma prevalence in our population.
Methods: We retrospectively analyzed 9,230 consecutive colonoscopies performed between 1996 and 2011 in a high-volume outpatient clinic in Cluj-Napoca, Romania. We analyzed 2,436 complete colonoscopies that detected 3,642 polyps in two time periods: 1996 to 2003 and 2004 to 2011. We compared the number, size and histopathological features of the polyps removed from the right-sided colon and the left sided-colon in the two periods.
Results: An increasing trend of polyp detection rate in the right-sided colon was observed, from 9.36% in the first period to 12.17% in the second period (p<0.001). The prevalence of right-sided colon adenomas also presented an increased trend (OR 1.45; CI95% 1.02-2.05; p=0.03). High-grade dysplasia (HGD) was found in 8.6% of the adenomas and in 4.1% of the diminutive polyps. Advanced neoplasia was detected in 1.5% of persons younger than 50 years. Multivariate logistic regression analysis evidenced that the right-sided polyps were significantly associated with the last time period (OR 1.3; p=0.001; CI95% 1.12-1.56), male gender (OR-1.3; p=0.001; CI95% 1.1-1.5) and age above 48 years (OR 1.3; p=0.006: CI95% 1-1.6).
Conclusion: An increasing trend of polyp detection rate in the right-sided colon was documented, with an increasing prevalence of right-sided adenomas. The evaluation of the proximal colon is particularly important in males aged over 48. A clear-cut risk of HGD in the diminutive polyps and in the middle age subjects has been also observed.