Large Intestine: Colon Cancer Screening
Colonoscopy Screening
General Colonoscopy Recommendations
- Start: Age 50
- *Some Societies are Moving to Age 45
- Repeat: Every 10 Years
- Stop: Age 76-85
- If First-Degree Relative Has Colon Cancer:
- Start: Age 40 or 10-Years Before the Age of Diagnosis
- Repeat: Every 5 Years
American Cancer Society (ACS)
- Start: Age 45
- *Previously Recommended Age 50
- Repeat: Every 10 Years
- Stop: Age 76-85
US Preventative Services Task Force (USPSTF)
- Start: Age 50
- *Draft Recommendation as of January 2021 will Change Starting Age to 45
- Stop: Age 76-85
World Gastroenterology Organization (WGO)
- Average Risk:
- Start: Age 50
- Repeat: Every 10 Years
- First-Degree Relative:
- Start at 40 or 10 Years Before Earliest Relative
- Relative < 60 or 2 First Degree Relatives: Every 5 Years
- Relative > 60: Every 10 Years
National Comprehensive Cancer Network (NCCN)
- Start: Age 50
- Repeat: Every 10 Years
- First-Degree Relative:
- Start: Age 40 or 10 Years Before Earliest Relative
- Repeat: Every 5 Years
Colonoscopy Contraindications
- Recent MI
- Pregnancy
- Splenomegaly
Colonoscope 1
Novel Screening Methods
General
- Contraindicated in High-Risk Patients
- Follow Up Any Positives with a Colonoscopy (The Gold Standard)
Fecal Testing
- Guaiac-Based Fecal Occult Blood Test (FOBT)
- Repeat: Every Year
- Procedure: Guaiac Test of Stool Sample Reacts to Peroxidase Activity of Heme (Detects Blood)
- Three Stool Samples Collected at Home – DRE Samples are Not Sensitive
- Considerations: High False-Negative & False-Positive Rates
- Sensitivity (One Time Use): 50-60%
- Higher Sensitivity if Repeated Every 1-2 Years
- Majority of Positive Tests are False Causing Unnecessary Interventions
- Sensitivity (One Time Use): 50-60%
- False Positive: Beef, Vitamin C, Iron, Cimetidine
- Fecal Immunochemical Test (FIT/IFOBT)
- Repeat: Every Year
- Procedure: Tests Feces for Hgb Using Highly-Sensitive Techniques
- Multi-Targeted Stool DNA Test (Cologuard)
- Repeat: Every 3 Years
- Procedure: Tests Stool Samples for Molecular Markers
- Considerations: Optimal Set of Molecular Markers Not Yet Determined & Low Sensitivity but Higher than FIT
- Sensitivity: 52-80%
- Specificity: 87%
CT Colonography (Virtual Colonoscopy)
- Repeat: Every 5 Years
- Procedure: CT Done with Air Insufflation for Colonic Distention & Oral Contrast to Allow Digital Subtraction of Fecal Material
- Considerations: Satisfactory for Large Polyps but Not for Small-Medium Polyps
- Large Polyps (≥ 10 mm):
- Sensitivity: 93%
- Specificity: 97%
- Medium & Large Polyps:
- Sensitivity: 86%
- Specificity: 86%
- All Polyps:
- Sensitivity: 45-97%
- Specificity: 26-97%
- Large Polyps (≥ 10 mm):
Flexible Sigmoidoscopy
- Repeat: Every 5 Years
- Considerations: Unable to View Right Colon
FIT Testing 2
CT Colonography 3
Pathology Considerations
Adenoma Repeat Testing – United States Multi-Society Task Force on Colorectal Cancer (2019)
- Hyperplastic Polyps (HP):
- < 10 mm: Normal Schedule
- ≥ 10 mm: 3-5 Years
- Tubular Adenomas:
- 1-2: 7-10 Years
- 3-4: 3-5 Years Mn
- 5-10: 3 Years
- > 10: 1 Year
- Advanced Adenoma: Repeat 3 Years
- Advanced Characteristics:
- Size ≥ 10 mm
- Tubulovillous or Villous Histology
- High-Grade Dysplasia
- Advanced Characteristics:
- Sessile Serrated Polyp (SSP):
- 1-2: 5-10 Years
- 3-4: 3-5 Years
- 5-10: 3 Years
- Advanced Characteristics: Repeat 3 Years
- Size ≥ 10 mm
- Any Dysplasia
- Traditional Serrated Adenoma (TSA)
- Resection in Piecemeal Fashion (≥ 20 mm): 6 Months to Ensure Complete Excision
Inflammatory Bowel Disease (IBD)
- Screening: Colonoscopy with Random Bx
- Start: 8-10 Years After Diagnosis
- Start Immediately If Concurrent PSC
- Repeat: Every 1-3 Years
- *See Large Intestine: Inflammatory Bowel Disease (IBD)
Hereditary Nonpolyposis Colon Cancer (HNPCC/Lynch Syndrome)
- Screening: Colonoscopy
- Start: Age 20-25
- Repeat: Every 1-2 Years
- Also Screening EGD After Age 35
- *See Oncology: Colorectal Cancer & Polyposis Syndromes
Familial Adenomatous Polyposis (FAP)
- Screening: Flexible Sigmoidoscopy
- Start: Age 10-12
- Repeat: Every Year
- Continue Even After Colectomy
- Also Screening EGD Every 2-3 Years After Age 25
- *Or Start Whenever Colon Polyps are Fist Seen – Whichever Comes First
- *See Oncology: Colorectal Cancer & Polyposis Syndromes
Colon CA Post-Resection
- Initial:
- If Entire Colon Was Seen at Prior Colonoscopy: 1 Year
- If Entire Colon Was Not Seen at Prior Colonoscopy: 6 Months
- Repeat: At 3 Years
- Other Measures:
- CEA Every 3-6 Months for 3-5 Years
- CT Chest/Abdomen/Pelvis Every Year for 3 Years
Mnemonics
Repeat Colonoscopy for Adenomas
- “3 at 3”
- *2012 Guidelines Recommended 3 Year Follow Up for 3-10 Adenomas but New Recommendations were Expanded
References
- Gilo 1969. Wikimedia Commons. (License: CC BY-SA-3.0)
- Schreuders EH, Grobbee EJ, Spaander MC, Kuipers EJ. Advances in Fecal Tests for Colorectal Cancer Screening. Curr Treat Options Gastroenterol. 2016 Mar;14(1):152-62. (License: CC BY-4.0)
- Yun JY, Ro HJ, Park JB, Choi JB, Chung JE, Kim YJ, Suh WH, Lee JK. Diagnostic performance of CT colonography for the detection of colorectal polyps. Korean J Radiol. 2007 Nov-Dec;8(6):484-91. (License: CC BY-NC-3.0)