Characteristics and Detection of Colorectal Polyps in Mongolia: A Single-Center Study

Aims Colorectal cancer (CRC) incidence in Mongolia has been steadily increasing, with over 300 new cases diagnosed annually. Colorectal polyps, particularly adenomatous polyps, are established precursors to CRC, and their early detection and precise characterization are essential for effective cancer prevention. This study aimed to analyze colorectal polyp characteristics—including size, location, histology, and patient demographics—to inform targeted screening and management strategies in Mongolia and ultimately improve patient outcomes.

Methods Data were collected retrospectively from 495 consecutive patients with colorectal polyps who underwent therapeutic endoscopic polypectomy at the IGIC Endoscopic Network in Mongolia between January 2023 and July 2024. Data were analyzed using RStudio version 1.3.1093 (Boston, MA, USA). Age and other continuous variables are presented as means±standard deviation (SD), while frequencies are presented as percentages. An independent two-sample t-test evaluated age differences by sex, and a chi-square test analyzed categorical variables.

Results A total of 495 patients were included, with a nearly equal sex distribution: 246 females (49.7%) and 249 males (50.3%) (p=0.892). The mean age of participants was 54.2 years (SD=12.2), with females averaging 56.3 years (SD=11.6) and males 52.1 years (SD=12.5), showing a statistically significant difference (p<0.001). Of the polyps, 45.5% were located proximally, while 67.5% were found distally, with the sigmoid colon being the most common site (24.7%). Regarding polyp size, 78.2% were 5 cm or smaller, 19.0% ranged from 6 to 9 cm, and 2.8% were 10 cm or larger (p<0.001). Histologically, a total of 383 neoplastic and 171 non-neoplastic polyps were identified across 495 patients, with some patients presenting with multiple polyps. Adenomatous polyps were the most prevalent, accounting for 65.7% of cases. Among these, the majority were tubular adenomas (91.8%), followed by tubulo-villous adenomas (7.0%) and villous adenomas (1.2%). Sessile serrated lesions, including sessile serrated polyps/adenomas (SSP/SSA), represented 11.7%. Hyperplastic polyps comprised 30.5% of cases, while other non-neoplastic polyps accounted for 4.0% of cases [1] [2] [3] [4] [5] [6].

Conclusions This study underscores the importance of polyp characteristics—such as size, location, histology, and patient demographics—in guiding early detection and management of colorectal polyps. The majority of polyps were located distally, with 78.2% measuring 5 cm or smaller. Adenomatous polyps, which carry a higher risk of malignant progression, were the most prevalent. These findings highlight the need for proactive diagnosis and personalized treatment approaches to reduce the risk of colorectal cancer. Early detection, based on polyp characteristics, is critical for improving patient outcomes and preventing progression. The insights from this study may help inform local screening guidelines and enhance colorectal cancer prevention strategies in Mongolia.

Publication History

Article published online:
27 March 2025

• References

• 1 Qumseya, Bashar J MD1; Coe, Susan MD1; Wallace, Michael B MD, MPH1. The Effect of Polyp Location and Patient Gender on the Presence of Dysplasia in Colonic Polyps. Clinical and Translational Gastroenterology 3(7):p e20, July. | doi:10.1038/ctg.2012.14
• 2 Øines M, Helsingen LM, Bretthauer M, Emilsson L. Epidemiology and risk factors of colorectal polyps. Practice pointsResearch agenda. Best Practice & Research Clinical Gastroenterology. 2017; doi:10.1016/j.bpg.2017.06.004
• 3 Center for Health Development. Health indicators – 2022. pp. 134-137 Ulaanbaatar, Mongolia: Center for Health Development of Mongolia; 2023
• 4 Mareth K, Gurm H, Madhoun MF. Endoscopic Recognition and Classification of Colorectal Polyps. Gastrointestinal Endoscopy Clinics of North America 2022; 32 (Issue 2): 227-240 ISSN 1052-5157, ISBN 9780323986731
• 5 Tanaka S, Saitoh Y, Matsuda T, Igarashi M, Matsumoto T, Iwao Y, Suzuki Y, Nozaki R, Sugai T, Oka S, Itabashi M, Sugihara KI, Tsuruta O, Hirata I, Nishida H, Miwa H, Enomoto N, Shimosegawa T, Koike K.. Evidence-based clinical practice guidelines for management of colorectal polyps. J Gastroenterol 2021; 56 (4): 323-335 Epub 2021 Mar 1233710392PMC8005396
• 6 Øines M, Helsingen LM, Bretthauer M., Emilsson L.. Epidemiology and risk factors of colorectal polypsPractice pointsResearch agenda Best Practice & Research Clinical Gastroenterology. 2017; doi:10.1016/j.bpg.2017.06.004.
• 7 Dornblaser D, Young S, Shaukat A.. Colon polyps: updates in classification and management. Curr Opin Gastroenterol 2024; 40 (1): 14-20 Epub 2023 Nov 1. PMID: 37909928