Do polyps smaller than 6 mm have a different prognosis depending on their macroscopic, topographical or histological characteristics?

Aims The natural history of small polyps is not well established. This study was conducted to describe the diagnostic and prognostic characteristics of the small colonic polyp less than 6 mm.

Methods This is a cross-sectional study extended over a period of 3 years from 2022 to 2024 including patients with colonic polyps. The data sources used were the anatomo-pathological reports. For each patient, the following parameters were included: sex, age, size and location of the polyp during colonoscopy. The anatomo-pathological characteristics were also determined.

Results 124 patients were included in our study. The average age was: 61.30 years±11.36. The majority of the population was male (n=86; 67.7%). Among 124 polyps 54 were diminutive (42.5%). Polyps less than 6 mm were adenomatous in 51.9% of the cases (n=28). Seven polyps (25%) were of advanced histological nature: with scalloped component (n=1; 3.5%), in high-grade dysplasia (n=5;17.8%) with adenocarcinoma lesions (n=1; 3.5%). Of the polyps≥6mm, 41 were of adenomatous type (58.1%): 17 polyps were advanced histological nature :14 polyps (20%) were with high-grade dysplasia, 2 polyps (2,9%) were scalloped, adenocarcinoma n=1 (1.4%). High-grade dysplasia is more frequent according to the size of the polyp. Non-diminutive polyps have a frequency of DHG which rises to 3% compared to diminutive polyps with a significant difference (P<0.001). In the rectum, the great majority of polyps less than 6 mm are of hyperplastic nature (n=22; 40.7%) or in low-grade dysplasia (n=20; 37%) apart from the rare cases of high-grade dysplasia (n=6; 11.1%) and a single case of adenocarcinoma n=1 (1.9%).

Conclusions Diminutive polyps, defined by a size less than 6 mm, are the most frequent polyps, whether they are adenomas in more than half of the cases (> 51%) of scalloped polyps or adenocarcinomas in some cases of rectal polyps.

Publication History

Article published online:
27 March 2025