Colonoscopy: Screening Can Save Your Life

The majority of colon cancers arise from growths of tissue called polyps. It is important to understand that there are two main histological types of polyps – adenomatous and hyperplastic. Hyperplastic polyps are benign and do not have the potential to become malignant; however, adenomatous polyps (also referred to as tubular adenomas) are also benign growths of tissue but have the potential to become malignant. When looking at colonoscopy screening/ surveillance intervals, the number, the size, and the histology of the polyps are taken into consideration. Screening just indicates the interval between colonoscopies when no adenomatous polyps are found. Surveillance indicates the interval between colonoscopies when adenomatous polyps are found.

Oftentimes, primary care physicians are the ones who monitor screening and surveillance intervals. We often get calls questioning when a patient is due for their next colonoscopy. There is also confusion about findings of hyperplastic polyps, as patients will tell their doctors that they had “polyps” on prior colonoscopies.

The importance of correct time intervals between colonoscopies cannot be emphasized enough. No one wants to go through this procedure more than what is indicated and insurance will not reimburse for unnecessary procedures. The following are guidelines agreed upon by the major gastroenterology societies and cancer society’s regarding colon cancer screening and surveillance.

  • Average risk screening is to be done at the age of 50.
  • If this does not show any adenomatous polyps, repeat colonoscopy in 10 years.
  • If polyps are present but histology comes back hyperplastic, repeat colonoscopy in 10 years.
  • Remember that we are only interested in adenomatous colon polyps in terms of determining colonoscopy intervals.
  • A first-degree relative with colon cancer necessitates an initial colonoscopy at age 40 or 10 years younger than the affected relative’s age of diagnosis.
  • Repeat colonoscopy every five years.
  • There is no definite consensus on how to evaluate patients with first-degree relatives who have colon polyps. We err on the side of caution and use the same guidelines as a first-degree relative with colon cancer.
  • A second-degree or third-degree relative with colon cancer or colon polyps follows average-risk screening guidelines.
  • Because of the increased risk of developing colon cancer with increased duration of the disease, patients with ulcerative colitis and Crohn’s disease should have surveillance colonoscopies every one to two years after eight to ten years of the disease.

There are also some special situations in which the screening/surveillance interval can be changed. Some examples are patients with a fair or poor bowel preparation or where a polyp is removed piecemeal. No matter what the situation, we maintain a logbook where we note when the patient’s next colonoscopy is due and send a reminder letter to the patient a few months prior to make an appointment. We are always available if there is a question or concern about colonoscopy intervals. We at The Jackson Clinic GI Department are committed to providing appropriate and timely colonoscopy screenings and surveillance and thus doing our part to decrease the incidence of colon cancer.

Patients with tubular adenomas will need surveillance colonoscopies depending on the characteristics of the polyps.

  • One to two tubular adenomas less than one centimeter in size – repeat in five years.
  • Three to ten tubular adenomas OR one tubular adenoma equal to or greater than one centimeter – repeat in three years.
  • Greater than ten tubular adenomas – repeat in one to three years.
  • A tubulovillous adenoma is an adenoma that is more advanced towards malignancy and is diagnosed by histology – repeat in three years.
  • Future colonoscopies are determined by thefindings of polyps. If two subsequent colonoscopies after the index colonoscopy showing polyps are negative, then the interval is lengthened to ten years. If subsequent colonoscopies also show polyps, the interval is three to five years based on surveillance guidelines.
  • No routine screening colonoscopy is recommended at or after the age of 75. If the patient is between the ages of 75 and 85 and in good health,surveillance colonoscopy is recommended.
  • No screening or surveillance colonoscopy is recommended after the age of 85.Dr. Ami Naik
  • The diagnosis of cancer is something that no one wants to hear. Unfortunately, for most cancers there are no preventative measures that can be taken. Colon cancer is one of the few malignancies for which there is a known screening measure that has been proven effective. Yet, we still have a long way to go. In the United States, only 60% of eligible people are being screened for colon cancer. It is estimated that one in 17 people will develop colon cancer and it is the third leading cause of cancer deaths in both men and women.