Colorectal Cancer Research Update
In the United States, colorectal cancer (CRC) is the third most common cancer diagnosed in men and women and the second leading cause of death from cancer. In 2008, it's estimated that 148,810 men and women will be diagnosed with CRC and 49,960 will die from this disease. However, five-year survival is 90 percent , if the disease is diagnosed while still localized, and recent trends in CRC incidence and mortality rates reveal declines (National Cancer Institute, 2009). As healthcare professionals, it is important to remain up to date with current developments, so here’s a quick scoop on the most recent developments in the screening and management of CRC.
New guidelines made headlines last month, when the U.S. Preventive Services Task Force, together with the American Cancer Society and the American College of Radiology released a new joint guideline: Screening and Surveillance for the Early Detection of Colorectal Cancer and Adenomatous Polyps, 2008. For the first time ever, the prevention of colorectal cancer (CRC) has been recognized as the primary goal of screening, rather than early detection. It is the strong opinion of this expert panel that colon cancer prevention tests, that are designed to detect both early cancer and adenomatous polyps, should be encouraged if resources are available and patients are willing to undergo an invasive test.
In another recent development, data from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer screening trial gives fresh insight into the appropriate screening intervals for colorectal cancer after a negative exam. An interim report published in the July 2008 issue of the Journal of the American Medical Association is the largest study to date of repeat sigmoidoscopy screening after an exam. The current accepted interval for sigmoidoscopy is five years after a negative exam. This recommendation is based primarily on indirect evidence. Exactly how often to repeat sigmoidoscopy is an evolving field of research. Whether data from the new study, which measures the incidence of growths or polyps three years after an initial exam, will play a role in changing the current five-year interval is still not clear, but be alert for the possible release of new recommendations soon.
Most public health organizations currently recommend that men and women at average risk begin colorectal cancer screening at age 50. Approximately 75 percent to 80 percent of colorectal cancers occur among people at average risk. People with a personal or family history of colorectal cancer or adenoma, or an illness predisposing them to colorectal cancer (e.g., inflammatory bowel disease), are considered at increased risk. They are advised to begin screening at an earlier age and may need to be tested more frequently.
Screening for CRC may include one or a combination of the following tests:
• Fecal occult blood test (FOBT): To detect small amounts of blood in the stool. The current recommended screening interval is every year.
• Sigmoidoscopy: Recommended screening interval is every five years.
• Colonoscopy: Recommended screening interval is every 10 years.
• Double contrast barium enema (DCBE): Recommended screening interval is every five years.
Virtual colonoscopy is another relatively new procedure that uses computerized tomography to visualize the colon. This test is also known as colonography or CT colonography. Clinical trials are currently comparing virtual colonoscopy with commonly used colorectal cancer screening tests to determine which are more accurate and cost effective.
In addition, some exciting new research now points the way to customizing chemotherapy regimes to match the genetic makeup of a tumor. Current research is focusing on searching for a tumor’s genetic signature, a unique pattern of gene and protein activity within a tumor that signals if the cancer will grow quickly or slowly, will be more or less likely to recur and which method of treatment it will be most responsive to. This is groundbreaking research in that custom profiling will allow treatment to be individualized to the extent that unnecessary interventions such as chemo, radiation and hormone therapy may be avoided, resulting in less pain and suffering without compromising the effectiveness of the therapy. The American Society of Clinical Oncology has estimated that this could save a stunning $600 million a year, by eliminating unnecessary drug therapy that may cost up to $10,000 a month, and not even work.
New CRC detection and treatment options are thus numerous and exciting, and ongoing clinical trials are producing some amazing findings. Make an effort to keep your practice up to date by periodically visiting the National Cancer Institute website at: http://www.cancer.gov/cancertopics/types/colon-and-rectal.
You can also improve your basic understanding of CRC by taking the two contact hour course on RN.com, entitled: Colorectal Cancer: Are You at Risk? This informative course provides basic information about the causes and management of CRC.