Colorectal Cancer Screening Guidelines Toolkit

Publication Date: February 27, 2024
Last Updated: February 29, 2024

Overview

Background

  • In the United States, colorectal cancer (CRC) is the fourth most common cancer diagnosed among adults and the second leading cause of death from cancer.
  • In the United States, CRC is most common in adults aged 65 to 74.
  • Incidence of CRC (specifically adenocarcinoma) in adults aged 40 to 49 years has increased by almost 15% from 2000-2002 to 2014-2016.In 2016, 25.6% of eligible adults in the US had never been screened for colorectal cancer5 and in 2018, 31.2% were not up to date with screening.
  • CRC remains the most preventable, yet least prevented, cancer.
  • CRC screening is the process of detecting early-stage CRCs and precancerous lesions in asymptomatic people with no prior history of cancer or precancerous lesions.
  • Regular CRC screening may help reduce mortality rates and has the potential to save lives.
  • The goal of screening is to reduce overall and cancer-specific morbidity and mortality using strategies that have acceptable harms, burden, and costs.
  • The typical pathogenesis of CRC is an adenomatous polyp that slowly increases in size and leads to dysplasia and cancer. Most CRC arises from colonic adenomas. However, 20% to 30% of CRC cases arise through pathways other than the adenoma–carcinoma sequence.
  • Progression from adenoma to invasive cancer varies from 5 years or less to more than 20 years. The 10-year cumulative risk for progression to carcinoma is about 10%; some adenomas stabilize and others regress. Progression risk is related to number, size, and histology of adenomatous polyps.
  • CRC screening should be performed as part of a population-based program that includes a systematic method for 1) identifying those who are eligible for and wish to undergo screening; 2) risk stratification and administration of the screening tests at agreed upon intervals; 3) shared decision-making with patients regarding the choice of screening method; 4) standardized reporting of the results; and 5) follow-up of those with a positive test. The program should also include a systematic method for the arranging of repeat screening and surveillance.

Guideline Synopsis

Current Guidelines

  • There have been over a half dozen clinical practice guidelines published in the United States alone on the topic of Colorectal Cancer Screening.
  • The guidelines agree on some points, and disagree or differ on others. There are multiple reasons for differing guidelines, including differences due to:
    • Differences in guideline scope — some guidelines focused on average risk only, while others included all patients and risk types.
    • Differences in methodology — for example, some guidelines are consensus, others GRADE.
    • Age and literature review timelines — spanning 2017 to 2022
    • Development from different medical vantage points, from primary care, to oncologists to gastroenterologists, to government agencies.

Overview

Title

Colorectal Cancer Screening Guidelines Toolkit

Authoring Organization