Masterclass: Colorectal Screening Plus (Virtual) | September 2025-Anderson Tool talk 9 22 25

Anderson Tool talk 9 22 25

Pdf Summary

This article discusses the impact of invasive screening modalities—flexible sigmoidoscopy and colonoscopy—on colorectal cancer (CRC) detection and success rates.<br /><br />Flexible sigmoidoscopy is performed without sedation, usually involves a Fleets enema for preparation, and visualizes the mucosa up to the descending colon. While it is less invasive and does not require a gastroenterologist, its use is decreasing due to reimbursement challenges, limited visualization (not full colon), and preference shifting toward colonoscopy. Guidelines recommend flexible sigmoidoscopy every 5 years starting at age 45.<br /><br />Colonoscopy offers full visualization of the colon, making it the preferred screening tool. However, it poses challenges such as incomplete exams, often due to anatomical factors like colon angulation, narrowing, redundancy, and patient characteristics such as age, sex, body habitus, prior surgeries, and diverticular disease. Women who are thin and older or have had hysterectomies can present particular challenges in insertion and completion rates.<br /><br />Technological advances in colonoscope design have been significant—options now include pediatric scopes, variable stiffness, wider viewing angles (170 degrees), water jets, and tapered insertion tubes. Studies comparing scope designs found that scopes with increased column strength and a tapered insertion tube length of 44 cm improve cecal intubation and retroflexion rates, reducing the need for maneuvers such as abdominal pressure or repositioning of patients.<br /><br />Data from large registries like the National Colorectal Cancer Roundtable (NHCR) involving over 350,000 exams have informed quality indicators such as adenoma detection rate (ADR) and withdrawal times.<br /><br />Looking forward, increasing obesity rates and widespread propofol sedation complicate positioning during colonoscopy, suggesting a need for continued innovation in scope design to facilitate complete exams and improve CRC screening effectiveness.

Keywords

colorectal cancer

flexible sigmoidoscopy

colonoscopy

screening modalities

adenoma detection rate

colon angulation

colonoscope design

cecal intubation

propofol sedation

obesity impact