MKSAP Quiz: evaluated after a colonoscopy
A 65-year-old man is evaluated after a recent colonoscopy, which disclosed a 2.5-cm pedunculated polyp in the sigmoid colon. The polyp was removed in its entirety in a single piece. Biopsy results showed a well-differentiated adenocarcinoma confined to the submucosa without evidence of lymphovascular involvement and a 1-mm margin. There is no family history of colorectal cancer. What is the most appropriate management?
A 65-year-old man is evaluated after a recent colonoscopy, which disclosed a 2.5-cm pedunculated polyp in the sigmoid colon. The polyp was removed in its entirety in a single piece. Biopsy results showed a well-differentiated adenocarcinoma confined to the submucosa without evidence of lymphovascular involvement and a 1-mm margin. There is no family history of colorectal cancer.
Physical examination findings are unremarkable.
Which of the following is the most appropriate management?
A. Colon resection
B. CT scan of the abdomen and pelvis
C. Radiation therapy
D. Repeat colonoscopy in 3 months
MKSAP Answer and Critique
The correct answer is D: Repeat colonoscopy in 3 months. This item is available to MKSAP 17 subscribers as item 57 in the Gastroenterology and Hepatology section. More information is available online.
The most appropriate management is to repeat colonoscopy in 3 months. A malignant polyp was discovered during this patient's colonoscopy and was endoscopically resected. Invasive adenocarcinoma arising in a pedunculated polyp may be considered adequately treated by endoscopic en bloc polypectomy alone if the lesion is confined to the submucosa and possesses no adverse histologic features such as poor differentiation, lymphatic or vascular invasion, or involved margins. National recommendations for postpolypectomy surveillance intervals are as short as 3 to 6 months in patients with large (>2 cm) adenomas or adenomas with invasive cancer and favorable prognostic features. These shorter surveillance intervals help to ensure that no residual polyp tissue remains.
If any adverse histologic features are noted, the risk of lymph node involvement is increased substantially and surgical resection of the involved colon is required. Surgical resection should also be considered if the lesion is removed piecemeal and the adequacy of resection cannot be confirmed.
Since this tumor is endoscopically cured, neither radiation therapy nor CT scan of the abdomen or pelvis is necessary.
Key Point
- National recommendations for postpolypectomy surveillance intervals are as short as 3 to 6 months in patients with large (>2 cm) adenomas or adenomas with invasive cancer and favorable prognostic features.