Novel Method for Screening Colorectal Neoplasm

Colorectal cancer (CRC) is one of the leading causes of cancer death worldwidewith themajority of cases having no previous family history. Themost effectiveway to reducemortality is to detect precancerous adenoma in an early stage. Several screening methods are now available; however as each modality has its limitation there is no superb strategy so far to conquer cancer death with colorectal cancer (Winawer et al., 1997). Fecal occult blood testing (FOBT) is the most widely employed screening tools, but sensitivity varies from 30% to 90% and depends on whether the specimens are rehydrated or not. The value of colonoscopy in screening can be appreciated, but it is costly and invasive. Moreover its effectiveness also depends on the endoscopist's skill. Computed tomographic colonoscopy (CTC)may anothermodality and rapidly evolving, but there are no controlled trials of screening CTC (Johnson et al., 2008). The risk of cumulative radiation exposure is also unknown. A special adaptation of capsule endoscopy has been developed to obtain images of the colon using tiny video cameras embedded in the two ends of an ingested capsule; however several studies have found a relatively low sensitivity for polyp detection (Rokkas et al., 2010). Current serum markers are not sufficiently sensitive or specific to be used for screening. The advent of 16S rRNA-based analyses has allowed investigation of the human colonic microbiota at the level of phylotypes and bacterial species (Shen et al., 2010). The rationale of this method applying for the colorectal cancer screening is intriguing. In the colon, trillions of commensal bacteria, termed the microbiota, are in close proximity to a single layer of epithelial cells. Evidence from animal and human studies suggests that intestinal commensal bacteria are not innocent bystanders but rather active participants in health. They contribute to the regulation of cell proliferation, differentiation and gene expression in host epithelial cells (Sanapareddy et al., 2012). Goedert et al. reported a very interesting research to address a new way of screening colorectal neoplasm (Goedert et al., 2015). They have created a cancer screening project in Shanghai area with combined methods of fecal immunohistochemical test (FIT), colonofiber and microbiota analysis. After informed consent was provided by 95 consecutive FIT positive patients, 61 patients had successful fecal microbiota profiling and colonoscopy. They confirmed 24 completely normal patients, 20 colorectal adenoma (CRA), 2 colorectal carcinoma and 15 with other conditions. Through the meticulous statistical analysis, they