What are the symptoms, malignant potential, and management options for adenomas in the sigmoid and transverse colon diagnosed via colonoscopy in a 75-year-old male?

From the Guidelines

Adenomas found in the sigmoid and transverse colon of a 75-year-old man during colonoscopy should be completely removed via polypectomy, as these are precancerous lesions that can progress to colorectal cancer over time. Most adenomas are asymptomatic, though larger ones may occasionally cause rectal bleeding, changes in bowel habits, or abdominal pain. The risk of malignant transformation depends on the adenoma's size, number, and histology, with larger (>1 cm), villous, and high-grade dysplastic adenomas carrying higher risk. Management includes complete endoscopic removal of all adenomas followed by surveillance colonoscopy, with intervals determined based on the findings, as suggested by 1. For low-risk findings, such as 1-2 small tubular adenomas, surveillance colonoscopy is typically recommended in 3 years, while high-risk findings may require more frequent surveillance, as indicated by 1. However, considering the patient's age, it is suggested that individuals who are up to date with screening and have negative prior screening tests, particularly high-quality colonoscopy, consider stopping screening at age 75 years or when life expectancy is less than 10 years, as recommended by 1. Lifestyle modifications including regular physical activity, maintaining healthy weight, limiting red meat and alcohol consumption, and avoiding smoking can help reduce recurrence risk, as generally recommended for reducing cancer risk. The patient should be informed that adenoma removal significantly reduces colorectal cancer risk, but ongoing surveillance is necessary as new adenomas may develop over time, as implied by the need for follow-up in 1. Key considerations in management include:

• Complete removal of adenomas to prevent malignant transformation
• Determining surveillance intervals based on adenoma characteristics and patient factors, such as life expectancy
• Lifestyle modifications to reduce recurrence risk
• Patient education on the importance of surveillance and the potential for new adenoma development, as supported by the guidelines in 1 and the recommendations for screening cessation in 1.

From the Research

Symptoms of Adenomas in the Sigmoid and Transverse Colon

• Adenomas in the sigmoid and transverse colon may not always present with symptoms, but when they do, they can include changes in bowel habits, abdominal pain, and bleeding 2, 3
• The progression of symptoms can be insidious, and tumors may be voluminous by the time of diagnosis 3

Malignant Potential of Adenomas

• Villous adenomas, a subtype of adenomas, have a higher risk of malignant transformation and are larger in size than tubular adenomas 2
• Carcinoma of the transverse colon accounts for 10% of all colorectal cancer, and diagnosis is often delayed 3
• The risk of cancer developing in adenomas is higher in larger lesions, and nearly half of all recurrent polyps occurred after at least one negative intervening examination 4

Management Options for Adenomas

• Colonoscopic removal of large, sessile polyps can be successfully carried out by experienced endoscopists, with a complication rate of 3.0% 4
• Therapeutic colonoscopy has replaced or lessened the need for traditional open surgical procedures, and can be used for hemostasis, resection and ablation of benign and malignant disease, decompression and recanalization of obstructed or dilated bowel, and foreign body extraction 5
• Surgical resection may be required in some cases, especially when invasive carcinoma is found in the specimen, and an aggressive regimen of surveillance colonoscopy is warranted to detect and manage local recurrences and to remove subsequent adenomas 4, 6

Follow-up and Surveillance

• Follow-up colonoscopy is essential to detect and manage local recurrences and to remove subsequent adenomas, with a median follow-up of 47.2 months 6
• The cancer diagnosis may have been delayed in some cases because of failed biopsy detection, and increased emphasis on identifying and completely removing all neoplastic lesions at colonoscopy may help avoid missed or incompletely removed lesions 6