Can a partial colectomy be performed for dysplasia in a patient with Primary Sclerosing Cholangitis (PSC)?

Management of Colonic Dysplasia in Patients with Primary Sclerosing Cholangitis

Total proctocolectomy is recommended for patients with PSC who have high-grade colonic dysplasia or neoplasia, while partial colectomy is generally not appropriate due to the high risk of malignant progression and multifocal nature of dysplasia in these patients. 1

Risk Assessment for Dysplasia in PSC Patients

PSC patients with inflammatory bowel disease (IBD) have a significantly elevated risk of colorectal cancer:

• 9-fold increased risk compared to the general population 1
• 10-fold increased risk compared to ulcerative colitis patients without PSC 1
• Right-sided predominance of neoplasia in up to 76% of cases 2

Management Algorithm for Dysplasia in PSC

For Visible Dysplastic Lesions:

1. Attempt endoscopic resection of any visible lesion
2. Assess surrounding mucosa with chromoendoscopy and targeted biopsies
3. Recommend proctocolectomy if:
   • Dysplasia is found in surrounding mucosa
   • Complete endoscopic resection is not possible
   • High-grade dysplasia is present 1

For Invisible Dysplastic Lesions:

1. High-grade dysplasia: Proctocolectomy is strongly recommended 1
2. Low-grade dysplasia:
   • Confirmed by two expert pathologists
   • Repeat colonoscopy with chromoendoscopy within 3 months
   • If persistent or multifocal, proctocolectomy should be considered 1

Evidence Supporting Total Proctocolectomy Over Partial Colectomy

The EASL clinical practice guidelines (2022) strongly recommend colectomy for:

• High-grade colonic dysplasia
• Neoplasia
• Persistent symptomatic colonic inflammation despite optimal medical therapy
• Low-grade dysplasia that is confirmed on multiple occasions and/or at multiple locations 1

Key considerations:

1. High progression rate: One-third of PSC-UC patients with low-grade dysplasia progress to high-grade dysplasia/cancer, with most progression occurring within the first year of diagnosis 3

2. Field effect: The entire colon is at risk due to the field effect of PSC-IBD, making partial colectomy inadequate for cancer prevention

3. Multifocal nature: Dysplasia in PSC-IBD tends to be multifocal and can occur in areas distant from the initial dysplastic lesion 1

Surgical Approaches

When colectomy is indicated, the recommended surgical approach is:

• Total proctocolectomy with ileal pouch-anal anastomosis (IPAA) is preferred over ileostomy 2
• Subtotal colectomy with ileosigmoid or ileorectal anastomosis may be considered in select cases with rectal-sparing disease, but requires rigorous endoscopic surveillance 4

Important Considerations and Caveats

1. Liver function assessment: Evaluate liver function before surgery, as patients with significant PSC may experience hepatic decompensation after colectomy 5, 6

2. Timing of surgery: For patients with advanced liver disease requiring both liver transplantation and colectomy, options include:

   • Simultaneous liver transplantation and colectomy
   • Liver transplantation first, followed by colectomy
   • Colectomy first in patients with well-controlled PSC 5

3. Pouch complications: Higher risk of pouchitis and pouch failure in PSC-IBD patients compared to IBD alone 1

4. Surveillance after surgery: Continued surveillance is necessary if any rectal mucosa remains 1, 2

5. Biliary dysplasia assessment: Consider evaluation for biliary dysplasia before surgery, as this may influence management decisions 7

In conclusion, while partial colectomy may be technically feasible, total proctocolectomy is the standard of care for PSC patients with colonic dysplasia due to the high risk of malignant progression and the multifocal nature of dysplasia in this patient population.