What is a hyperplastic polyp in the colon?

From the Guidelines

A hyperplastic polyp in the colon is a common, non-cancerous growth that protrudes from the lining of the colon, typically small, pale, and with a smooth surface, and has very little to no potential to develop into colorectal cancer, as stated in the guidelines by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society 1.

Key Characteristics of Hyperplastic Polyps

• They are the most common type of colon polyp, accounting for about 90% of all colon polyps
• They develop due to excessive cell growth in the colon's lining
• They are often found during routine colonoscopies, particularly in the rectum and sigmoid colon (the lower parts of the large intestine)
• Most hyperplastic polyps don't require treatment beyond removal during colonoscopy for confirmation

Important Considerations

• Some larger hyperplastic polyps (greater than 10mm) or those found in the right side of the colon may need closer monitoring, as they may be at higher risk for developing into colorectal cancer 1
• The presence of multiple or large hyperplastic polyps might indicate a condition called hyperplastic polyposis syndrome, which carries an increased risk of colorectal cancer, as noted in the guidelines 1
• Regular colonoscopy screenings are recommended for early detection and removal of all types of colon polyps, with follow-up intervals determined by the patient's risk factors and the results of the initial colonoscopy 1

Surveillance Recommendations

• Patients with small rectal hyperplastic polyps should be considered to have normal colonoscopies, and therefore the interval before the subsequent colonoscopy should be 10 years, unless they have a hyperplastic polyposis syndrome 1
• Patients with only one or two small (<1 cm) tubular adenomas with only low-grade dysplasia should have their next follow-up colonoscopy in 5 to 10 years, based on other clinical factors such as prior colonoscopy findings, family history, and patient preferences 1

From the Research

Definition and Characteristics of Hyperplastic Polyps

• Hyperplastic polyps are typically small, sessile polyps (5 mm) located in the rectosigmoid area 2
• They are the most frequent nonneoplastic lesions of the colon 2
• Hyperplastic polyps can be large (20 mm in size) and are difficult to distinguish from other types of polyps 2
• They are usually considered to be an innocent finding with little or no potential to progress to colorectal cancer, but recent literature suggests that some of these polyps may be morphologically and genetically distinct and lead to microsatellite unstable colorectal cancers 3, 4

Relationship between Hyperplastic Polyps and Colorectal Cancer

• Patients with hyperplastic polyposis are at high risk for colorectal cancer, with 54% of patients developing colorectal cancer during the study period 3
• Hyperplastic polyps may serve as the precursor of colorectal cancer with DNA methylation and deficient DNA mismatch repair, particularly in the proximal colon 4
• The presence of multiple hyperplastic polyps, especially in the right colon, may be associated with an increased risk of colorectal cancer 3, 4

Diagnosis and Treatment of Hyperplastic Polyps

• Hyperplastic polyps can be diagnosed using narrow band imaging (NBI) or chromoendoscopy, which may improve the detection of polyps in patients with hyperplastic polyposis syndrome 5
• Large hyperplastic polyps can be removed by endoscopic polypectomy on an outpatient basis without complications 2
• Patients with hyperplastic polyposis should undergo regular colonoscopic surveillance with removal of all detected polyps to prevent the development of colorectal cancer 5, 3