Endoscopic Submucosal Dissection for the Complete Resection of the Rectal Remnant Mucosa in a Patient With Familial Adenomatous Polyposis.

A 47-year-old woman underwent prophylactic subtotal colectomy with ileorectal anastomosis (IRA) for familial adenomatous polyposis (FAP) 18 years ago. She underwent 5 transanal endoscopic microsurgeries for rectal remnant polyps, and was referred for the treatment of rectal remnant polyp recurrence. Endoscopic submucosal dissection (ESD) was performed to remove multiple polypoid lesions that circumferentially extended throughout the rectal remnant with lesions spreading onto the anastomotic site. The rectal remnant mucosa was resected in 2 pieces without complication. Specimens showed high-grade adenoma but no malignancy. Follow-up colonoscopy showed no recurrence.

Introduction

Subtotal colectomy with ileorectal anastomosis (IRA) is occasionally performed for patients with familial adenomatous polyposis (FAP) rather than total proctocolectomy with ileal pouch-anal anastomosis (IPAA), because it produces better functional outcomes and decreases the infertility rate after surgery., However, neoplasms that occur in the rectal remnant after IRA require additional treatments, including secondary proctectomy. Endoscopic submucosal dissection (ESD) has recently been performed to treat superficial neoplasms of the digestive tract.-

Case Report

A 47-year-old woman underwent prophylactic subtotal colectomy with IRA for FAP 18 years ago. She then underwent 5 separate transanal endoscopic microsurgeries (TEMs) for the removal of subsequent rectal remnant polyps. Proctoscopy revealed multiple polypoid lesions in the rectal remnant (Figure 1). Biopsy specimens from the polypoid lesions showed high-grade adenoma. Because the polyps circumferentially extended throughout the rectal remnant with the oral portion of the lesions spreading onto the anastomotic site, circumferential ESD was planned for the complete resection of the rectal remnant mucosa.

Figure 1

Endoscopic view of polypoid lesions extending throughout the rectal remnant.

Although the submucosal dissection at the anastomotic site was difficult because of severe fibrosis, the rectal remnant mucosa was completely resected in 2 pieces without perforation using a KD-620LR hook knife (Olympus Medical Systems, Center Valley, PA; Figure 2). Pathology examination of the resected specimens demonstrated high-grade, non-cancerous adenoma. Post-ESD stricture was prevented using a betamethasone suppository and finger bougie. Follow-up proctoscopy performed 12 months after the circumferential ESD showed no recurrence in the rectal remnant (Figure 3). Rectal mucosa was completely replaced by ileal mucosa and the bowel function of the patient was not exacerbated.

Figure 2

Endoscopic view of (A) severe fibrosis and surgical staples at the anastomotic site, (B) the post-ESD ulcer in the rectal remnant, and (C) the post-ESD ulcer in retroflexion. (D) The resected specimens meausred 36 × 27 mm and 10 × 10 mm.

Figure 3

Follow-up proctoscopy 12 months after ESD showed rectal mucosa was completely replaced by ileal mucosa and no recurrence in the rectal remnant.

Discussion

FAP is an autosomal dominant disease characterized by more than hundreds of adenomatous polyps. FAP increases the risk of colon cancer, and prophylactic colectomy is required to prevent the further development of colon cancer. Colectomy can be either subtotal colectomy with IRA or total proctocolectomy with IPAA. Total proctocolectomy with IPAA is more difficult to perform, and can result in impaired bowel function and an increased risk of infertility. Thus, subtotal colectomy with IRA is preferred, especially in younger patients., However, neoplasms can occur in the rectal remnant after IRA, requiring additional endoscopic treatments and/or secondary proctectomy.

In cases such as ours, where many polyps spread onto the anastomotic site and throughout the rectal remnant, treatment by endoscopic mucosal resection (EMR) using snare is difficult. Because ESD has been performed for the resection of large gastrointestinal neoplasms with negligible risk of metastasis,- we decided to perform circumferential ESD for the resection of the rectal remnant mucosa. Although severe fibrosis was observed within the submucosal layer at the anastomotic and post-TEM sites, use of a hook knife enabled precise submucosal dissection of the fibrotic tissues and completion of circumferential ESD without perforation. Stricture following circumferential ESD can be managed with steroid suppositories and finger bougies. We suggest that circumferential ESD is a safe and effective treatment for complete resection of the rectal remnant mucosa after IRA in patients with FAP.

Disclosures

Author contributions: The authors contributed equally to the creation of this manuscript. N. Ishii is the article guarantor.

Financial disclosure: None to report.

Informed consent was obtained for this case report.

This case report was presented as a poster at the ACG Annual Scientific Meeting; October 16-25, 2015; Honolulu, Hawaii.