What is a colectomy and when is it recommended?

Colectomy: Definition and Clinical Indications

What is a Colectomy?

Colectomy is the surgical removal of all or part of the colon (large intestine), performed through various techniques including subtotal colectomy (removal of most of the colon with preservation of the rectum), total colectomy (removal of the entire colon), or segmental resection (removal of a specific portion). 1, 2 The procedure can be performed via open surgery or minimally invasive laparoscopic/robotic approaches, with the anastomosis typically completed extracorporeally through a small incision. 3

Emergency Indications

Emergency colectomy is immediately required for life-threatening complications and should not be delayed. 1

Fulminant Clostridioides difficile Colitis

• Total colectomy with end ileostomy is the procedure of choice for fulminant C. difficile infection. 1
• Perform emergency surgery for: colonic perforation, systemic inflammation not responding to antibiotics, toxic megacolon, or severe ileus. 1, 4
• Operate before serum lactate exceeds 5.0 mmol/L to prevent mortality. 1
• Diverting loop ileostomy with colonic lavage is an alternative to preserve the colon, though reoperation may be needed in 15.9% of cases. 1

Acute Severe Ulcerative Colitis

• Subtotal colectomy with ileostomy is recommended for patients with acute severe UC who fail medical therapy within 7 days or develop complications (perforation, severe hemorrhage, toxic megacolon). 1
• Delay in surgery increases surgical complications and mortality—patients requiring colectomy beyond 6 days have 2-3 times higher mortality risk. 1
• A staged procedure (initial subtotal colectomy) is mandatory in patients taking ≥20 mg prednisolone daily for >6 weeks or those treated with anti-TNF therapy. 1
• Laparoscopic approach is preferred when appropriate surgical expertise is available, resulting in fewer wound infections and shorter hospital stays. 1

Urgent Indications

Inflammatory Bowel Disease (Non-Emergency)

• For hospitalized UC patients with continued symptoms after 7 days of maximal medical therapy (including rescue therapy with infliximab or ciclosporin), subtotal colectomy with ileostomy should be performed. 1, 5
• Subtotal colectomy allows patients to regain health, normalize nutrition, and definitively excludes Crohn's disease on pathology. 1
• The rectal remnant should be divided at the recto-sigmoid junction (promontory level), not within the pelvis, to facilitate future surgery and reduce pelvic nerve injury risk. 1

Elective Indications

Chronic Ulcerative Colitis

• Offer surgical resection to patients with chronic active UC symptoms despite optimal medical therapy. 1
• Proctocolectomy with ileal pouch-anal anastomosis (IPAA) provides excellent quality of life, with 95% of patients reporting good or excellent outcomes at 10 years. 1
• Pouch surgery should be performed in specialist high-volume centers (>100 procedures) to minimize pouch failure rates (5.2% vs higher in low-volume centers). 1
• For females requiring emergency subtotal colectomy, discuss proctectomy and IPAA timing due to potential fertility impairment. 1

Lynch Syndrome with Colorectal Cancer

• Colectomy with ileorectal anastomosis is the primary treatment for Lynch syndrome patients with colon cancer or non-removable neoplasia. 1
• The 10-year cumulative risk of metachronous colorectal cancer is 16-19% after partial colectomy versus 3.4% after subtotal/total colectomy. 1
• Consider less extensive surgery in patients >60-65 years or those with sphincter dysfunction. 1
• For rectal cancer in Lynch syndrome, total proctocolectomy with IPAA should be discussed given the 69% cumulative cancer risk at 30 years. 1

Dysplasia in Inflammatory Bowel Disease

• Colectomy is mandatory for flat high-grade dysplasia, which carries a 42-67% risk of synchronous colorectal cancer. 1
• For flat low-grade dysplasia, strongly consider colectomy if: detected on multiple occasions, multifocal (>1 site), or found at initial screening (prevalent dysplasia). 1
• Adenoma-like dysplastic lesions within inflamed areas can be managed by polypectomy and continued surveillance if no flat dysplasia exists in adjacent mucosa. 1

Other Malignant and Benign Conditions

• Subtotal colectomy is indicated for colon cancer with: acute/subacute obstruction (when proximal colon cannot be evaluated), synchronous carcinomas, multiple polyps, or age <50 with positive family history. 6
• Benign indications include familial polyposis syndrome, severe diverticular disease, and rectal prolapse. 2, 3

Critical Pitfalls to Avoid

• Never delay surgery in acute severe colitis beyond 7 days of failed medical therapy—prolonged admission is the only significant predictor of postoperative complications. 1
• Avoid leaving minimal rectum (<2 cm from dentate line) during subtotal colectomy, as this increases pelvic nerve injury risk during subsequent proctectomy. 1
• Do not perform IPAA in high-risk patients (weight loss >10%, albumin <3.0 g/dL, significant immunosuppression)—perform staged subtotal colectomy first. 5
• Always use a covering loop ileostomy when performing restorative proctocolectomy to minimize anastomotic leak complications. 1