Advances in endoscopy for colorectal polyp detection and classification.
Advances in endoscopy for colorectal polyp detection and classification. Proc (Bayl Univ Med Cent). 2020 Jan;33(1):28-35 Authors: Pamudurthy V, Lodhia N, Konda VJA Abstract While colonoscopy is considered the gold standard for colon cancer screening, recent advancements in endoscopes have allowed for improved visualization of the colonic mucosa and improved polyp detection rates. Newer technologies also allow for assessment of structural changes for polyp discrimination and determination of histologic type. Classification of polyps prevents the need for a histopathologic report, which requires the additional time and expertise of a pathologist and adds to the overall cost. This review considered advances in endoscopic technologies reported in PubMed over the past 12 years. Technologies that allow for increased visual field of colonic mucosa and may lead to improved colon polyp detection rates include cap-assisted colonoscopy, RetroView, extra-wide-angle view colonoscope, full-spectrum endoscopy, Third Eye Retroscope, NaviAid G-EYE balloon colonoscope, EndoRings, and Endocuff. Image-enhancing methods allow for pit pattern analysis of colorectal lesions, which enables the physician to classify colorectal polyps according to certain polyp characteristics. Image-enhancing methods include chromoendoscopy, autofluorescence, and virtual chromoendoscopy, including narrow band imaging, i-SCAN, flexible spectral imaging chromoendoscopy, and STORZ professional imag...
CONCLUSION: A hybrid robotic transanal minimally invasive surgery approach allows for complete resection of very large polyps, which would otherwise be extremely challenging with standard transanal approaches. See Video at http://links.lww.com/DCR/B231.
This study was designated to explore the role of cancer stem cells (CSCs) during chemically induced mouse colon carcinogenesis (by 1,2- dimethylhydrazine dihydrochloride, DMH) with/or without the treatment with a targeted (anti-COX-2) therapeutic drug, celecoxib. Two experiments were conducted. The first, a short-term, 16-week mouse colon carcinogenesis bioassay, demonstrates the early stages of colon carcinogenesis. The other is a medium-term, 32-week mouse colon cancer experiment that mimics an end point of colon malignancy. Colon tumors were detected in animals after 32 weeks; histopathologically, they varied from benig...
AbstractPurpose of ReviewParticipation goals for colorectal cancer (CRC) screening in the USA have not been met. Non-invasive screening strategies may improve CRC screening participation. We highlight recent literature on stool-based screening performance and expectations for emerging non-invasive screening tests.Recent FindingsStool-based CRC screening detects screen-relevant colorectal neoplasia and outperforms a currently available plasma assay. Though modestly sensitive for CRC, adherence to annual fecal immunochemical testing (FIT) is sub-optimal. Multi-target stool DNA (MT-sDNA) has greater adherence, superior sensit...
Colonoscopic removal of adenomatous polyps has a preventive effect for colorectal cancer. Cold snare polypectomy is an effective method of polyp removal for small polyps (5 mm to 10 mm). Endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) is used for larger polyps (>10 mm). Submucosal injection during EMR or ESD is helpful to prevent complications. However, the effect of submucosal injection in cold snare polypectomy for small polyps is not clear. The aim of this study is to evaluate the risks of bleeding in cold snare polypectomy for small polyps and to investigate the effect of submucosal injection.
Postpolypectomy bleeding and incomplete polyp removal are important complication and quality concerns of colonoscopy for colon cancer prevention. Endoscopic mucosal stripping (EMS) is a modified extension of traditional cold snare polypectomy to avoid submucosal injury during removal of non-pedunculated colon polyps. We previously demonstrated EMS could potentially eliminate postpolypectomy bleeding, especially for advanced colon polyps, and facilitate complete polyp removal based on polypectomy site biopsy and short-term follow-up colonoscopy (1,2).
We reported retrospective data that compared with CO2 insufflation, water exchange (WE) colonoscopy significantly reduced rAMR (17.5% vs. 33.8%, P=0.034) (BMC Gastroenterol 2019;19:143). We performed a prospective randomized controlled trial (RCT) of WE and CO2 insufflation to determine whether WE with near-complete removal of infused water during insertion could reduce rAMR and rAMR combined with right colon hyperplastic polyp miss rate (rHPMR).
A net-work meta-analysis (GIE. 2018;88:589) showed water exchange (WE) provided the highest adenoma detection rate (ADR). The impact on sessile serrated polyp detection rate (SSPDR) was not addressed. SSP have increased malignant potential (Curr Treat Options Gastroenterol. 2015;13:156). They have subtle appearance (AJG. 2012;107:1315). They cluster in the proximal colon (61%) (Arch Pathol Lab Med. 2015;139:388) co-localizing with interval cancers (64% to 68%) (Gastro. 2014;146:950; Cancer. 2012;118:3044).
Most colorectal cancers originate from colon polyps that develop from normal tissue after an initial set of molecular events ends controlled mucosal regeneration. The molecular events that initiate polyp development depend on inherited and life style factors, age of the patient as well as random chance effect. Therefore, the distribution of polyp number per patient may adhere to a probability distribution.
The incidence of colon and rectal cancer (CRC) is rising in the US in individuals younger than 50 years. The American Cancer Society published a qualified recommendation to begin CRC screening at age 45. Bowel preparation is a recognized barrier to screening or diagnostic colonoscopy. Outcomes of bowel preparation have not been widely studied in individuals