Should Colon Polyps Be Removed?
Yes, colon polyps should be removed because they are precursors to colorectal cancer, and their removal has been proven to reduce both cancer incidence and mortality. 1
Evidence for Polyp Removal
The rationale for removing colon polyps is firmly established:
The National Polyp Study provided the strongest evidence that removal of polyps reduced the risk of subsequent colorectal cancer, with long-term follow-up demonstrating a reduction in mortality after polyps were removed during screening colonoscopy 1
Screening sigmoidoscopy and removal of polyps reduced colorectal cancer mortality in studies from the early 1990s 1
Colorectal polyps are the precursors for most colorectal cancers, as dysplastic elements can invade the submucosa and allow for lymphatic and vascular metastasis 1
Size-Based Removal Guidelines
Polyps ≥10 mm
- All polyps ≥10 mm must be removed because they have significantly higher malignant potential and warrant 3-year surveillance after removal 2, 3
Polyps 5-9 mm
- Polyps 5-9 mm should be removed 1
- The Japan Polyp Study Group demonstrated that patients with polyps measuring 6-9 mm have a cumulative hazard of developing invasive cancer comparable to those with intramucosal cancer 1
- Cold snare resection is appropriate for polyps ≥5 mm 4
Diminutive Polyps (<5 mm)
- Small distal hyperplastic polyps in the rectum/sigmoid <10 mm require no surveillance beyond routine 10-year screening intervals, though removal at the time of detection is still standard practice 2
- Approximately 70-80% of polyps are diminutive (≤5 mm) and almost never contain cancer, though they are typically removed when detected 4
Type-Specific Considerations
Adenomatous Polyps
- All adenomatous polyps (tubular, tubulovillous, or villous) should be completely removed 1, 5
- Even tubular adenomas <1 cm can harbor invasive cancer, though the risk is lower 5
- Villous adenomas have the highest malignant potential and must be removed 5
Serrated Polyps
- Sessile serrated polyps (SSPs) ≥10 mm or any SSP with dysplasia warrant removal and 3-year surveillance 2
- Traditional serrated adenomas (TSAs) require removal and 3-year surveillance 2
- Small hyperplastic polyps <10 mm without dysplasia may not require intensive surveillance but are typically removed when detected 2
Malignant Polyps
- Malignant polyps (cancer invading submucosa) require complete endoscopic removal with careful pathologic assessment 1
- If completely resected with favorable histologic features (grade 1-2, no lymphovascular invasion, negative margins), no additional surgery may be required 1
- Unfavorable features (grade 3-4, lymphovascular invasion, positive margins, submucosal invasion >1 mm) necessitate surgical resection with lymph node removal 1
Critical Technical Points
Complete Resection is Essential
- Polyps should be resected en bloc whenever possible to allow proper pathologic assessment 1
- Piecemeal resection increases the risk of incomplete removal and recurrence, particularly for large polyps 6
- Sessile adenomas removed piecemeal should have 6-month follow-up to verify complete removal 3
Referral Considerations
- Large polyps (≥20 mm) or those with high difficulty of resection should be referred to endoscopists with advanced resection expertise 1, 6
- Advanced techniques (endoscopic mucosal resection, endoscopic submucosal dissection) may be needed for complex lesions 6
Common Pitfalls to Avoid
- Never leave a polyp in place simply because it appears benign endoscopically—8% of endoscopically benign-appearing large polyps contain cancer on final pathology 7
- Ensure proper specimen handling: large pedunculated lesions should not be cut to facilitate removal through the suction channel, as this prevents proper pathologic assessment 1
- Mark the polyp site with tattoo if cancer is suspected or within 2 weeks of polypectomy when pathology confirms malignancy (except cecal polyps) 1
- Do not assume small size equals safety: invasive cancer has been found even in polyps <1 cm in diameter 5