Treatment and Follow-up Options after Colon Cancer

Bradley Somer, MD
Last Modified: November 1, 2001

Dear OncoLink "Ask the Experts,"
Would appreciate your help and guidance. My wife under went a colon resection to remove cancerous growth. One lymph node tested positive. Subsequent chemotherapy treatment (5 FU & leucovorin ) administered over a six-month period.

What are the follow up testing procedures?
What are the follow up treatment procedures?
What preventative measures are recommended?

I would appreciate your assistance with my request.

Bradley Somer, MD, OncoLink Editorial Assistant, responds:

To review: Your wife had colon resection and there was 1 node with tumor. Presuming that there is no further evidence of disease or metastases, and that the surgeon was able to remove the tumor with adequate margins in its entirety, your wife was given adjuvant chemotherapy (for no current detectable disease, but rather to prevent relapse from the risk of micrometastasis). This would most likely be considered a Duke's stage C or Stage III (AJCC) colon cancer.

With resection alone for colon cancer is curative in 50% of patients. After resection, adjuvant chemotherapy is given in situations where patients are more likely to relapse. The intent is to prevent future recurrence of disease. Patients with lymph node involvement are candidates for this therapy. Patients with colon cancer with other higher risk features such as perforation, obstruction, aggressive pathological features and invasion of any internal organs are potential candidates for adjuvant chemotherapy. The main data on adjuvant chemotherapy in this setting is in patients with lymph node involvement (stage III).

There have been multiple major clinical trials including those from the Intergroup, NSABP, and the NCCTG showing significant benefit from adjuvant chemotherapy. In general, the extra benefit obtained from chemotherapy is 22-30% for Stage III patients. Standard therapy is with 5-FU/levamisole or 5-FU/leucovorin. This is the mainstay of preventive strategies for recurrence. Other therapeutic adjuvant chemotherapy strategies are under investigation.

After therapy, patients are typically followed closely to ensure that should recurrence happen, it is discovered early, thus improving the ability to manage it effectively. Some of the aspects and timing of the studies required to follow up are controversial. The National Comprehensive Cancer Network has published guidelines and the following is adopted from that with some modifications.

  • Every 3 months for 2 years, then every 6 months for 5 years:
    • Medical history focusing on weight loss, weakness, loss of appetite, constipation, nausea, vomiting, fevers and abdominal pain.
    • Physical exam focusing on weight, lymph node evaluation, abdominal bloating, tenderness, masses, liver enlargement, rectal masses, or stool for occult blood testing.
    • Blood counts
  • CEA (Carcinoembronic antigen)-only if elevated prior to or just after surgery. If by following it and the patient does relapse, they would be a candidate for surgical resection of discovered localized recurrence or isolated metastasis. (Every 6 months for 2 years, then annually for 5 years.)
  • Chest X-ray: for stage B2 or C disease- every 12 months for 5 years
  • Abdominal CT scan: approximately every 6 months for 2 years, then annually for 3 years.
  • Colonoscopy within the first year, then repeat 1 year later and every 3 years after that if negative for multiple synchronous polyps or if the patient has a new polyp on surveillance colonoscopy.
These recommendations remain controversial and we recommend following a surveillance protocol as outlined by your individual skilled oncologist.