From the Guidelines
For a patient with a positive Cologuard test after successful treatment and surgery for colon cancer, the next step should be a diagnostic colonoscopy performed by a gastroenterologist or colorectal surgeon. This follow-up colonoscopy is essential to visually examine the colon and directly investigate the abnormality detected by the screening test, as recommended by the American Society of Clinical Oncology clinical practice guideline endorsement 1. During the procedure, the physician will look for any new polyps, recurrent cancer, or other abnormalities, and can take biopsies of suspicious areas. The colonoscopy should be scheduled promptly, ideally within 1-3 months of the positive Cologuard result.
Following this, the patient will likely need more intensive surveillance than the general population, typically with colonoscopies every 1-3 years depending on findings and risk factors, rather than the standard 10-year interval, as suggested by the US Multi-Society Task Force on Colorectal Cancer 1. This closer monitoring is necessary because patients with a history of colon cancer have a higher risk of developing new cancers or experiencing recurrence. The patient should also continue regular follow-up visits with their oncologist and surgeon according to their established survivorship care plan, which may include periodic blood tests for carcinoembryonic antigen (CEA) and imaging studies to monitor for recurrence, as recommended by the American Society of Clinical Oncology 1.
Some key points to consider in the follow-up care of these patients include:
- A medical history, physical examination, and CEA testing should be performed every 3 to 6 months for 5 years 1
- Abdominal and chest imaging using a CT scan is recommended annually for 3 years 1
- A surveillance colonoscopy should be performed approximately 1 year after the initial surgery, and the frequency of subsequent surveillance colonoscopies should be dictated by the findings of the previous one 1
- Any new and persistent or worsening symptoms warrant the consideration of a recurrence 1
From the Research
Next Steps for a Patient with a Positive Cologuard Result
After successful treatment and surgery for colon cancer, a positive Cologuard result indicates the presence of abnormal cells or blood in the stool, which may suggest a recurrence of colon cancer or the development of new precancerous or cancerous growths. The next steps for such a patient would involve further diagnostic testing to determine the cause of the positive result.
Diagnostic Testing
- Colonoscopy: This is a crucial test for patients with a history of colon cancer, as it allows for the visualization of the entire colon and the removal of any polyps or suspicious tissue for biopsy 2, 3.
- Imaging studies: CT scans or other imaging tests may be used to evaluate the liver, lungs, and other areas for signs of cancer spread 4.
- Blood tests: These may include tests for carcinoembryonic antigen (CEA) levels, which can be elevated in patients with colon cancer recurrence 5.
Surveillance and Follow-up
- Regular follow-up appointments: Patients with a history of colon cancer should have regular follow-up appointments with their healthcare provider to monitor for signs of recurrence and to discuss any concerns or symptoms 5.
- Surveillance colonoscopy: The frequency of surveillance colonoscopy will depend on the individual patient's risk factors and medical history, but it is generally recommended at intervals of 1-3 years 2, 3.
Prognostic Factors
- Pathologic features: The pathology report from the initial surgery can provide important prognostic information, including histologic grade, vascular invasion, and margin status 6.
- Tumor markers: Elevated levels of tumor markers such as CEA can indicate a higher risk of recurrence 5.
Management of Recurrence
- Surgical resection: If a recurrence is detected, surgical resection may be possible, especially if the recurrence is localized 5.
- Other treatments: Other treatments, such as chemotherapy or radiation therapy, may also be considered, depending on the location and extent of the recurrence.