What is the next best step in management for a 58-year-old man with a near-obstructing sigmoid colon adenocarcinoma and no evidence of metastatic disease?

Management of Near-Obstructing Sigmoid Colon Adenocarcinoma

Surgical resection followed by adjuvant chemotherapy is the optimal management for a 58-year-old man with a near-obstructing sigmoid colon adenocarcinoma without evidence of metastatic disease. 1

Rationale for Surgical Resection as First-Line Treatment

The British Journal of Cancer guidelines clearly establish that the standard treatment for non-metastatic colon cancer includes excision of the primary tumor with safe margins and removal of associated lymphatic channels and nodes 1. For this patient with a sigmoid mass, the appropriate procedure would be a sigmoidectomy or anterior resection of the rectosigmoid.

Key considerations supporting immediate surgical resection include:

• Patient has clinical symptoms (change in bowel habits, abdominal pain, weight loss) indicating disease progression
• Near-obstructing lesion poses risk for complete obstruction if not addressed promptly
• CT shows no evidence of metastatic disease, making curative resection feasible
• Patient's age and presentation suggest he would tolerate definitive surgical intervention

Surgical Approach

The surgical procedure should include:

• Median laparotomy incision
• Thorough examination of liver, pelvis, and other potential metastatic sites
• Sigmoidectomy with adequate margins
• Lymph node dissection of the associated mesocolon
• Primary anastomosis if bowel preparation and vascular supply are adequate 1

If the tumor has invaded neighboring organs, an en bloc resection should be performed 1.

Post-Surgical Adjuvant Therapy

Following successful resection, adjuvant chemotherapy is indicated if pathology confirms stage III disease (lymph node involvement). The standard regimen consists of:

• 6-month course of 5-fluorouracil (5-FU) and folinic acid (FA) 1
• Alternative modern regimens include FOLFOX (5-FU, leucovorin, and oxaliplatin) 2

For stage II disease, adjuvant chemotherapy may be considered if high-risk features are present (such as T4 lesion, poor differentiation, lymphovascular invasion, or bowel obstruction) 1.

Why Not Other Options?

1. Neoadjuvant chemotherapy is not the standard approach for non-metastatic colon cancer, unlike rectal cancer. The primary tumor should be removed first to prevent complete obstruction and obtain accurate pathological staging 1.

2. Endoscopic stent placement is primarily reserved for:

   • Palliative management in metastatic disease 1
   • Temporary relief of obstruction in high-risk patients who cannot tolerate immediate surgery 1
   • This patient has no metastatic disease and appears fit for surgery, making stenting less appropriate.

3. Emergency surgery would be indicated if complete obstruction or perforation were present, but this patient has a near-obstructing lesion without signs of perforation or complete obstruction, allowing for proper preoperative preparation 1.

Special Considerations

• Proper bowel preparation is essential for successful anastomosis 1
• Mechanical and manual techniques for anastomosis yield similar results in experienced hands 1
• If the tumor is found to be locally advanced during surgery, an en bloc resection should be performed 1
• Careful pathological assessment will determine the need for adjuvant therapy based on staging

By following this approach, the patient has the best chance for both immediate symptom relief and long-term survival with optimal quality of life.