Is a tubular adenoma of the colon a serious condition?

From the Guidelines

A tubular adenoma of the colon is a potentially serious condition that requires medical attention but is not immediately life-threatening. It is a type of precancerous polyp that can develop into colorectal cancer if left untreated, though this progression typically takes years. The standard treatment is complete removal of the adenoma through colonoscopy polypectomy, which is usually curative. After removal, follow-up colonoscopies are necessary according to guidelines based on the size, number, and characteristics of the adenoma - typically ranging from 3-5 years for low-risk adenomas to shorter intervals for high-risk features, as recommended by the 2020 US Multi-Society Task Force on Colorectal Cancer 1. Some key points to consider include:

• The risk of the adenoma depends on factors like size (larger than 1 cm is higher risk), presence of high-grade dysplasia, and villous components.
• Most tubular adenomas are discovered during routine colonoscopy screenings, which is why regular colorectal cancer screening is recommended beginning at age 45 for average-risk individuals.
• The follow-up interval after removal of 1–2 tubular adenomas <10 mm in size is recommended to be 7- to 10-y rather than 5- to 10-y 1.
• While concerning as a precancerous lesion, when detected and removed early, the prognosis is excellent with appropriate surveillance. The importance of high-quality baseline examination has been emphasized, and the option to recommend 3–5 y instead of 3-y follow-up after removal of 3–4 adenomas <10 mm in size is available 1. Overall, the management and follow-up of tubular adenomas should be individualized based on the patient's specific risk factors and the characteristics of the adenoma, with the goal of preventing the development of colorectal cancer and improving patient outcomes.

From the Research

Tubular Adenoma of the Colon

• A tubular adenoma of the colon is a type of neoplastic polyp that has the potential to become malignant 2, 3.
• The risk of malignancy in tubular adenomas is related to factors such as polyp size, with larger polyps having a higher risk of malignant change 2, 3.
• The incidence of malignancy in tubular adenomas also rises parallel to the frequency of synchronous and metachronous polyps 2.

Characteristics of Tubular Adenomas

• Tubular adenomas are the most common type of neoplastic polyp found in the colon, with the largest number found in the sigmoid colon 2.
• They can be found in all zones of the colon, but are most frequently found in the sigmoid and descending colon 2.
• The risk of malignization in tubular adenomas is lower than in villous adenomas, but still present 3.

Risk Factors for Malignant Transformation

• Patient age, polyp size, and morphology are significant risk factors for malignization in tubular adenomas 3.
• A family history of colorectal cancer may also increase the risk of developing colorectal adenomas, including tubular adenomas 4.
• The presence of high-grade dysplasia in a tubular adenoma is a significant risk factor for the development of further adenomas with high-grade dysplasia or carcinoma 5.

Clinical Implications

• The detection and removal of colorectal polyps, including tubular adenomas, can help reduce the incidence of colorectal cancer 2, 3.
• Close follow-up is warranted for patients with a history of tubular adenomas, particularly those with high-grade dysplasia or large polyps 5.
• The possibility of metastatic tumors in colonic adenomatous polyps, including tubular adenomas, should also be considered in the clinical evaluation of these lesions 6.