Tx and Followup:
Polyp was biopsed and patient received appropriate follow-up care. No other information was documented
Although not all colon polyps will develop into colon cancer, almost all sporadic colon cancer arises from mucosal colonic polyps. Histology of the polyps is a critical parameter determining malignant potential with virtually all colon cancers believed to arise from adenomas. Killing approximately 60,000 Americans per year, colon cancer is the second leading cause of cancer-related mortality in the United States. Clinical trials have shown that the incidence and mortality from colon cancer can decrease with early detection and removal of premalignant adenomatous polyps. Appropriate colon cancer screening, therefore is important to prevent colon cancer and is recommended for all adults over 50 years old. Nonetheless, despite this evidence, less than one fourth of the eligible population in the United States participates in any method of colon cancer screening.
Currently conventional colonography is the primary screening test used to detect colonic polyps and cancers. Many barriers prevent individuals from receiving colonoscopy, including expense, invasiveness, patient discomfort, need for sedation and analgesia, and test risks. The introduction of virtual colonoscopy (CT colonography) in 1994 by Vining was to maintain the desirable features of colonoscopy of ease of lesion detection while avoiding the undesirable features as described above. Since 1994, there has been significant progress and development of virtual colonoscopy, making the procedure a viable alternative in screening the general population for colon cancer. Currently, various institutions worldwide perform virtual colonoscopy on an elective basis. With its many advantages, this technique may encourage more adults to seek testing. Some of these advantages include: lack of sedation, minimal invasiveness, rare test complications, detection of extracolonic abnormalities, and convenience, taking 15 minutes or less. However, unlike conventional colonoscopy, virtual colonoscopy is not therapeutic and requires a follow-up procedure with conventional colonoscopy for identified polyps.
Virtual colonoscopy is currently under intense analysis in order to establish the procedure as a primary screening method. There have been three recent multicenter virtual colonoscopy clinical trials published, which report widely divergent results primarily due to differences in CT technology, adjunctive techniques, CT colonographic interpretation, and study design. This patient was in a prospective multi-center trial published in 2003 by Pickhardt et al, which evaluated the use of virtual colonoscopy as a screening tool compared with traditional colonoscopy. In this study, researchers performed both conventional and virtual colonoscopy in 1,233 asymptomatic adults, 97.4 percent of whom were at average risk of having colonic polyps. Pickhardt and associates reported a sensitivity of 93.8% for polyps at least 10 mm in diameter, 93.9% for polyps at least 8mm in diameter, and 88.7% for polyps at least 6mm in diameter. Subsequently, for conventional colonoscopy, the sensitivity was 87.5%, 91.5%, and 92.3% respectively for these three categories of polyp size. In this study, virtual colonoscopy also detected two malignant polyps while conventional colonoscopy missed one of them. With these results, Pickhardt et al demonstrated that virtual colonoscopy is an excellent screening test for colonic polyps and rivals conventional colonoscopy. Furthermore, a metaanalysis on the accuracy of virtual colonoscopy by Sosna et al in 2003 revealed that virtual colonoscopy is an accurate tool for detecting clinically important colorectal polyps, that is, polyps that are greater or equal to 10 mm. The future of virtual colonoscopy is promising. When the accuracy, reliability, and cost-effectiveness of virtual colonoscopy is established in detecting polyps and cancers, this method has the potential to improve patient participation in screening programs and help decrease the impact of colorectal cancer.