Happy 2013 to all! As we begin the New Year, many of us have good intentions to follow through on our resolutions which may include losing weight, finishing projects we’ve put off, quitting smoking, and making more time for your family. There is one New Year’s resolution that I hope everyone over the age of 50 considers — colon cancer screening.
Despite a recent overall decrease of 3% in new cases of colorectal cancer, it is still the second most common cause of cancer-related deaths, only to be outdone by lung cancer. The National Cancer Institute estimates the cost of colorectal cancer care at roughly $12 billion in 2006, or approximately 12% of total cancer care cost. One in 20 men and women will be diagnosed with cancer of the colon or rectum during their lifetime. Considering the baby boomer generation is fast approaching 70 million, this translates into 3,500,000 cases!
What is so magical about age 50? 90% of all colorectal cancer diagnoses occur at age 50 or older. It is estimated that if every person over the age of 50 had a colonoscopy performed, 10,000 deaths could be prevented each year. Yet only 62% of adults over the age of 50 in California have colorectal cancer screening performed. For Hispanics, it’s less than 52%. Almost 70% of adults without a primary care provider have never had colon cancer screening. We need to do better.
What are my options? Options for screening for colorectal cancer include stool based and endoscopic/radiologic tests. The screening interval for adults over the age of 50 is 10 years for colonoscopy; whereas it is five years for flexible sigmoidoscopy, virtual colonoscopy, and double contrast barium enema (or x-ray of the colon); and annually for a fecal occult blood test.
There are exceptions, however, in adults who are considered higher risk: 1) adults with a 1st degree relative with a history of colorectal cancer or a high risk adenoma (precancerous polyp) before age 60; 2) two 1st degree relatives with history of colorectal cancer or a high risk adenoma regardless of age; and 3) African-Americans. For the first two groups, it is recommended that screening begin at age 40 or at 10 years before the age at diagnosis in youngest relative, and the interval be every 5 years. Because African-Americans tend to present with more advanced cancers and high risk adenomas at an earlier age, screening should begin at age 45, with a 10 year interval.
A stool-based test is a two-step approach to screening, which will require endoscopy if the test is positive. Fecal immunological test (FIT) is a new test that has demonstrated better performance and will most likely replace the more familiar guaiac-based test. This is because it is able to detect bleeding in smaller amounts.
Colonoscopy is a one-step approach that is considered the “gold standard.” It has the advantage of evaluating the entire colon, with the highest accuracy as it is a “visual” test. If done properly by a skilled endoscopist with adequate sedation, it is surprisingly quick and well tolerated.
Flexible sigmoidoscopy does not evaluate the proximal colon, but it is an acceptable screening option, as only 3% of patients with a known tumor in the distal colon will have a tumor in the proximal colon. However, in higher risk patients, colonoscopy should be considered. Since women have a slightly higher incidence of proximal tumors, colonoscopy may also be a better screening option.
CT colonography, or “virtual colonoscopy”, is a relatively newer technological option for screening. Its accuracy decreases for tumors less than 1 centimeter in size, and a “positive” test will require a colonoscopy to make a diagnosis. Though it has been endorsed by the American Cancer Society, it is not included in guidelines published by the American College of Physicians (ACP) and the US Preventative Services Task Force (USPSTF). Furthermore, it is not covered by most insurers as a primary screening tool. It is, however, an option for individuals in which colonoscopy is contraindicated.
Double contrast barium enema studies detect only 30-50% of cancers detected by colonoscopy and, subsequently, is no longer included in ACP and USPSTF guidelines.
Capsule endoscopy is an emerging option currently under investigation in the United States. Although it is utilized in Europe, its accuracy is not yet as good as colonoscopy.
What happens if I have a positive test? The whole basis of screening is to make a diagnosis early enough for cure. If a high risk adenoma is found and removed entirely after colonoscopy, then repeat colonoscopy should be performed in 3-5 years. If it is a large adenoma that cannot be removed by colonoscopy, has features worrisome for underlying cancer, or actual cancer, surgery is recommended. Traditionally, surgery involved making a large opening in the abdomen to remove the cancer. Unfortunately, due to the inherent invasive nature of an open procedure, there are significant associated complications, as well as a prolonged recovery. Fortunately, laparoscopic surgery has evolved in the last 10 years as a safe alternative method with no compromise on the conduct of surgery. Laparoscopic colorectal surgery has shown a significant decrease in complications (incisional hernia, bowel obstruction, transfusion requirements, to name a few), shorter hospital stay (3-5 days), more patients going home without additional nursing care, and quicker recovery (weeks versus months).
Be kind to man’s best friend. On a final note, in Japan, a Labrador dog was trained to sniff out colon cancer from breath and stool samples. Surprisingly, detection was 91% for breath tests and 100% for stool samples! Now I am not suggesting we replace physicians with dogs, but this does lead us to consider technologies that can mimic this dog’s olfactory skill. In the meantime, as we approach Colon Cancer Awareness in the month of March, we should stick to the recommended options – and schedule your screening today! Until next issue!
Dr. David Johnson is a board-certified general surgeon with Premier Surgical Associates in Palm Springs and can be reached at 760.424.8224. He is an advocate for early detection through colon cancer screenings. For more information, visit the American Cancer Society at www.cancer.org.