What is the recommended monitoring plan for a patient with colorectal cancer (colorectal Ca) status post (S/P) right hemicolectomy (R hemicolectomy)?

Post-Right Hemicolectomy Surveillance for Colorectal Cancer

For a patient with colorectal cancer after right hemicolectomy, implement stage-specific surveillance with clinical visits and CEA testing every 3 months for stages II-III disease during the first 2-3 years, combined with annual CT imaging and colonoscopy at 1 year post-resection. 1, 2

Surveillance Schedule by Disease Stage

Stage I Disease

• Clinical visits every 6 months for 5 years including physical examination with emphasis on digital rectal examination 1
• CEA testing at each visit 1
• Liver ultrasound examination at each visit 1
• Annual chest-abdomen-pelvis CT only if CEA or ultrasound abnormalities detected 1

Stage II-III Disease (Most Common Post-Hemicolectomy)

• Clinical visits every 3 months for the first 3 years, then every 6 months until year 5, then annually thereafter 1, 2
• CEA testing at each visit (every 3 months for 2 years, then every 6 months for years 3-5) 1, 2, 3
• CT imaging of chest, abdomen, and pelvis every 6-12 months for the first 3 years 1, 2
  • For high-risk patients (Stage IIIB with N2a disease), imaging every 6 months is reasonable given 80% of recurrences occur within 2-2.5 years 2
  • Annual imaging for 3 years is the minimum standard 2

Stage IV Disease (After R0 Resection of Metastases)

• Clinical visits every 3 months for 3 years, then every 6 months until year 5, annually thereafter 1
• CEA testing at each visit 1
• Contrast-enhanced chest-abdomen-pelvis CT every 6-12 months 1
• Abdominal-pelvic ultrasound examination 1

Colonoscopy Surveillance Protocol

Colonoscopy within 1 year after surgery is mandatory 1, 4, 3. The specific timing depends on preoperative clearance:

• If preoperative colonoscopy was complete: colonoscopy at 1 year post-resection 1
• If tumor obstruction prevented preoperative colonoscopy: colonoscopy at 3-6 months post-resection to clear synchronous disease 1, 4

Subsequent colonoscopy intervals 1:

• If 1-year colonoscopy is normal: repeat in 3 years
• If that examination is normal: repeat in 5 years
• If progressive adenomas found (tubulovillous, >1 cm, or high-grade dysplasia): repeat within 1 year 1
• If no progressive adenomas: repeat within 3 years, then every 5 years 1

Physical Examination Focus

At each visit, emphasize 1:

• Digital rectal examination (critical for detecting anastomotic recurrence)
• Abdominal examination for hepatomegaly or masses
• Assessment of surgical site and lymph node basins

Important Caveats and Clinical Pitfalls

When NOT to Perform Surveillance

Do not perform routine surveillance if the patient cannot tolerate curative-intent surgery or systemic chemotherapy due to severe comorbidities 2. Surveillance is only justified when intervention for recurrence is feasible 1.

PET/CT Use

PET/CT is NOT recommended for routine surveillance 1, 2, 4. Reserve PET/CT only for:

• Clinical suspicion of recurrence when routine imaging is negative 1
• Persistent CEA elevation without identifiable lesion on CT 1, 2
• Before surgical resection of suspected isolated resectable recurrence 2, 4

Emerging Technologies

ctDNA monitoring shows promise for early recurrence detection but remains controversial for routine use and treatment guidance 1. It is not yet standard of care.

Testing for Previously Elevated Markers

If tumor markers other than CEA were elevated preoperatively (CA 19-9, CA 125), test these at the same intervals as CEA 1.

Rationale for Intensive Surveillance

The evidence supporting intensive surveillance is based on 5, 6:

• Approximately 25% of Stage I-II patients and 40% of Stage II-III patients develop recurrence despite curative-intent surgery
• Most recurrences (80%) occur within the first 2-2.5 years, and 95% by 5 years 2, 6
• Early detection allows curative-intent resection in select patients with isolated recurrences 7, 6

However, the benefit must be weighed against increased costs, more invasive testing, and higher reoperation rates 5. This is why surveillance should only be performed in patients who are surgical candidates 2.