-
World Journal of Gastroenterology May 2020In recent years, the serrated neoplasia pathway where serrated polyps arise as a colorectal cancer has gained considerable attention as a new carcinogenic pathway.... (Review)
Review
In recent years, the serrated neoplasia pathway where serrated polyps arise as a colorectal cancer has gained considerable attention as a new carcinogenic pathway. Colorectal serrated polyps are histopathologically classified into hyperplastic polyps (HPs), sessile serrated lesions, and traditional serrated adenomas; in the serrated neoplasia pathway, the latter two are considered to be premalignant. In western countries, all colorectal polyps, including serrated polyps, apart from diminutive rectosigmoid HPs are removed. However, in Asian countries, the treatment strategy for colorectal serrated polyps has remained unestablished. Therefore, in this review, we described the clinicopathological features of colorectal serrated polyps and proposed to remove HPs and sessile serrated lesions ≥ 6 mm in size, and traditional serrated adenomas of any size.
Topics: Adenoma; Clinical Decision-Making; Colectomy; Colon; Colonic Polyps; Colorectal Neoplasms; Humans; Hyperplasia; Intestinal Mucosa; Narrow Band Imaging; Practice Guidelines as Topic; Precancerous Conditions; Proctectomy; Rectum; Treatment Outcome
PubMed: 32476792
DOI: 10.3748/wjg.v26.i19.2276 -
The Surgical Clinics of North America Jun 2017Difficult colorectal polyps represent lesions that pose a challenge to traditional endoscopic snare polypectomy. These polyps have historically been managed by surgical... (Review)
Review
Difficult colorectal polyps represent lesions that pose a challenge to traditional endoscopic snare polypectomy. These polyps have historically been managed by surgical resection. Currently, several less invasive options are available to avoid colectomy. Repeat colonoscopy and snare polypectomy by an expert endoscopist, endoscopic mucosal resection, endoscopic submucosal dissection, and combined endoscopic and laparoscopic surgery have been developed to remove difficult polyps without the need for formal surgical resection. Patients with rectal polyps have the advantage of additional transanal minimally invasive techniques to enhance their resectability. Today, most colorectal polyps can be managed without the need for formal surgical resection.
Topics: Colonic Polyps; Colonoscopy; Endoscopic Mucosal Resection; Humans; Laparoscopy; Neoplasm Invasiveness; Precancerous Conditions
PubMed: 28501244
DOI: 10.1016/j.suc.2017.01.003 -
Der Internist Jun 2013Preneoplastic lesions of colorectal carcinoma can be divided in non-serrated and serrated lesions. Non-serrated lesions include conventional adenomas (tubular,...
Preneoplastic lesions of colorectal carcinoma can be divided in non-serrated and serrated lesions. Non-serrated lesions include conventional adenomas (tubular, tubulovillous and villous) and dysplasias associated with inflammatory bowel disease like flat intraepithelial neoplasia, dysplasia-associated lesions or masses (DALM) and adenoma-like masses (ALM). Conventional adenomas are mostly sporadic, but also found in hereditary adenomatous-polyposis syndromes. Hamartous polyposis syndromes are also associated with colorectal cancer. Serrated lesions include hyperplastic polyps, sessile serrated adenomas and traditional serrated adenomas. Based on these precancerous colorectal lesions different molecular subtypes were identified. Histological subtype, size and grade of dysplasia of polyps are essential for risk assessment of colorectal cancer.
Topics: Colonic Polyps; Colorectal Neoplasms; Humans; Precancerous Conditions
PubMed: 23677564
DOI: 10.1007/s00108-012-3213-4 -
Surgery For Obesity and Related... Oct 2021Multiple studies have linked obesity to an increased risk of cancer. The correlation is so strong that the national cancer prevention guidelines recommend weight loss...
BACKGROUND
Multiple studies have linked obesity to an increased risk of cancer. The correlation is so strong that the national cancer prevention guidelines recommend weight loss for patients with obesity to reduce their risk of cancer. Bariatric surgery has been shown to be very effective in sustained weight loss. However, there have been mixed findings about bariatric surgery and its effects on the risk of colorectal cancer.
OBJECTIVE
This study sought to examine bariatric surgery patients and their risk of pre-cancerous or cancerous polyps to elucidate any risk factors or associations between bariatric surgery and colorectal cancer.
SETTING
A retrospective review of the academic medical center's bariatric surgery database was performed from January 2010 to January 2017. Patients who underwent medical or surgical weight loss and had a subsequent colonoscopy were included in the study. Positive colonoscopy findings were described as malignant or premalignant polyps.
METHODS
A total of 1777 patients were included, with 1360 in the medical group and 417 in the surgical group. Data analysis included patient demographics, co-morbidities, procedure performed, surgical approach, weight loss, and colonoscopy findings. A multivariate analysis was used to determine whether an association exists between weight loss and incidence of colorectal polyps, and if so, whether the association different for medical versus surgical weight loss.
RESULTS
A higher percentage of body mass index (BMI) reduction was seen in the surgical group. An overall comparison showed average reductions in BMI of 27.7% in the surgical group and 3.5% in the medical group (P < .0001). Patients with the greatest reduction in BMI, regardless of medical or surgical therapy, showed a lower incidence of precancerous and cancerous polyps (P = .041).
CONCLUSION
This study offers a unique approach in examining the incidence of colorectal polyps related to obesity. Patients with the greatest reduction in their BMI, more common in the surgical group, had a lower incidence of precancerous and cancerous polyps.
Topics: Bariatric Surgery; Colonic Polyps; Colonoscopy; Humans; Incidence; Obesity; Retrospective Studies; Weight Loss
PubMed: 34294588
DOI: 10.1016/j.soard.2021.06.005 -
Gastroenterology May 2024One goal of colorectal cancer (CRC) screening is to prevent CRC incidence by removing precancerous colonic polyps, which are detected in up to 50% of screening... (Review)
Review
One goal of colorectal cancer (CRC) screening is to prevent CRC incidence by removing precancerous colonic polyps, which are detected in up to 50% of screening examinations. Yet, the lifetime risk of CRC is 3.9%-4.3%, so it is clear that most of these individuals with polyps would not develop CRC in their lifetime. It is, therefore, a challenge to determine which individuals with polyps will benefit from follow-up, and at what intervals. There is some evidence that individuals with advanced polyps, based on size and histology, benefit from intensive surveillance. However, a large proportion of individuals will have small polyps without advanced histologic features (ie, "nonadvanced"), where the benefits of surveillance are uncertain and controversial. Demand for surveillance will further increase as more polyps are detected due to increased screening uptake, recent United States recommendations to expand screening to younger individuals, and emergence of polyp detection technology. We review the current understanding and clinical implications of the natural history, biology, and outcomes associated with various categories of colon polyps based on size, histology, and number. Our aims are to highlight key knowledge gaps, specifically focusing on certain categories of polyps that may not be associated with future CRC risk, and to provide insights to inform research priorities and potential management strategies. Optimization of CRC prevention programs based on updated knowledge about the future risks associated with various colon polyps is essential to ensure cost-effective screening and surveillance, wise use of resources, and inform efforts to personalize recommendations.
Topics: Humans; Colonic Polyps; Colonoscopy; Colorectal Neoplasms; Early Detection of Cancer; Risk Factors; Risk Assessment
PubMed: 38224860
DOI: 10.1053/j.gastro.2023.11.305 -
World Journal of Gastroenterology Aug 2021Colorectal cancer remains a leading cause of morbidity and mortality in the United States. Advances in artificial intelligence (AI), specifically computer aided... (Review)
Review
Colorectal cancer remains a leading cause of morbidity and mortality in the United States. Advances in artificial intelligence (AI), specifically computer aided detection and computer-aided diagnosis offer promising methods of increasing adenoma detection rates with the goal of removing more pre-cancerous polyps. Conversely, these methods also may allow for smaller non-cancerous lesions to be diagnosed and left in place, decreasing the risks that come with unnecessary polypectomies. This review will provide an overview of current advances in the use of AI in colonoscopy to aid in polyp detection and characterization as well as areas of developing research.
Topics: Adenoma; Artificial Intelligence; Colonic Polyps; Colonoscopy; Colorectal Neoplasms; Humans
PubMed: 34447227
DOI: 10.3748/wjg.v27.i29.4802 -
World Journal of Gastroenterology Aug 2018Sessile serrated adenoma/polyps (SSA/Ps) are early precursor lesions in the serrated neoplasia pathway, which results in colorectal carcinomas with mutations,... (Review)
Review
Sessile serrated adenoma/polyps (SSA/Ps) are early precursor lesions in the serrated neoplasia pathway, which results in colorectal carcinomas with mutations, methylation for DNA repair genes, a CpG island methylator phenotype, and high levels of microsatellite instability. Some of these lesions can rapidly become dysplastic or invasive carcinomas that exhibit high lymphatic invasion and lymph node metastasis potentials. Detecting serrated lesions, including SSA/Ps with and without dysplasia/carcinoma, is critical, but SSA/Ps can be difficult to detect, are inconsistently identified by endoscopists and pathologists, and are often incompletely resected. Therefore, SSA/Ps are considered to be major contributors to "interval cancers". If colonoscopists can identify the specific endoscopic characteristics of SSA/Ps, their detection and the effectiveness of colonoscopy may improve. Here, the endoscopic features of SSA/Ps with and without dysplasia/carcinoma, including the characteristics determined using magnifying endoscopy, are reviewed in the context of previous reports. Endoscopically, these subtle polyps are like hyperplastic polyps, because they are slightly elevated and pale. Unlike hyperplastic polyps, SSA/Ps are usually larger than 5 mm, frequently covered by a thin layer called the ''mucus cap'', and are more commonly located in the proximal colon. Magnifying narrow-band imaging findings, which include dark spots inside the crypts and varicose microvascular vessels, in addition to the type II-open pit patterns detected using magnifying chromoendoscopy, effectively differentiate SSA/Ps from hyperplastic polyps. The lesions' endoscopic characteristics, which include their (semi)pedunculated morphologies, double elevations, central depressions, and reddishness, and the use of magnifying endoscopy, might help to detect dysplasia/carcinoma within SSA/Ps. Greater awareness may promote further research into improving the detection, identification, and complete resection rates of SSA/Ps with and without dysplasia/carcinoma and reduce the interval cancer rates.
Topics: Adenoma; Colon; Colonic Polyps; Colonoscopy; Colorectal Neoplasms; Humans; Hyperplasia; Mutation; Narrow Band Imaging; Precancerous Conditions; Proto-Oncogene Proteins B-raf
PubMed: 30090005
DOI: 10.3748/wjg.v24.i29.3250 -
IEEE Journal of Biomedical and Health... Jul 2022Colorectal cancer (CRC) is a common and lethal disease. Globally, CRC is the third most commonly diagnosed cancer in males and the second in females. The most effective...
Colorectal cancer (CRC) is a common and lethal disease. Globally, CRC is the third most commonly diagnosed cancer in males and the second in females. The most effective way to prevent CRC is through using colonoscopy to identify and remove precancerous growths at an early stage. The detection and removal of colorectal polyps have been found to be associated with a reduction in mortality from colorectal cancer. However, the false negative rate of polyp detection during colonoscopy is often high even for experienced physicians. With recent advances in deep learning based object detection techniques, automated polyp detection shows great potential in helping physicians reduce false positive rate during colonoscopy. In this paper, we propose a novel anchor-free instance segmentation framework that can localize polyps and produce the corresponding instance level masks without using predefined anchor boxes. Our framework consists of two branches: (a) an object detection branch that performs classification and localization, (b) a mask generation branch that produces instance level masks. Instead of predicting a two-dimensional mask directly, we encode it into a compact representation vector, which allows us to incorporate instance segmentation with one-stage bounding-box detectors in a simple yet effective way. Moreover, our proposed encoding method can be trained jointly with object detector. Our experiment results show that our framework achieves a precision of 99.36% and a recall of 96.44% on public datasets, outperforming existing anchor-free instance segmentation methods by at least 2.8% in mIoU on our private dataset.
Topics: Colonic Polyps; Colonoscopy; Colorectal Neoplasms; Female; Humans; Male; Neural Networks, Computer
PubMed: 35104234
DOI: 10.1109/JBHI.2022.3147686 -
Expert Review of Gastroenterology &... Sep 2017Colonoscopy and endoscopic removal of precancerous polyps play an important role in colorectal cancer (CRC) prevention. Improved endoscopes and quality standards have... (Review)
Review
Colonoscopy and endoscopic removal of precancerous polyps play an important role in colorectal cancer (CRC) prevention. Improved endoscopes and quality standards have led to an increasing polyp and adenoma detection rate. Optimal polyp resection techniques and management strategies are key for an effective colonoscopy practice. Areas covered: Strategies for how to improve diminutive polyp (polyps up to 5 mm in size) management are discussed because of their high prevalence. Systematic removal of diminutive polyps leads to increasing costs of colonoscopy practice, while the effect on colorectal cancer prevention might be negligible. Furthermore, polypectomy recommendations for mid-size and large polyps are provided. For all larger polyps larger, complete and safe resection is mandatory to avoid post colonoscopy cancers. The focus for managing such larger polyps is to use new techniques (i.e. cold snares) and to attempt complete removal and to reduce post-polypectomy complications. Expert commentary: The resect-and-discard strategy is a promising management strategy for diminutive polyps. However, modification of this approach might be required in order to make widespread adoption feasible. Cold snare polypectomy is a promising new approach for small polyp resection. For resection of large polyps adequate treatment recommendations with regard to endoscopic mucosal resection and complication prevention are provided.
Topics: Colonic Polyps; Colonoscopy; Colorectal Neoplasms; Endoscopic Mucosal Resection; Humans; Precancerous Conditions
PubMed: 28319429
DOI: 10.1080/17474124.2017.1309279 -
Future Oncology (London, England) Apr 2022Colorectal cancer is the third most common cancer worldwide. Because of the slow progression of the precancerous precursors, an efficient endoscopic surveillance... (Review)
Review
Colorectal cancer is the third most common cancer worldwide. Because of the slow progression of the precancerous precursors, an efficient endoscopic surveillance strategy may be expected. It seems that around one-fourth of colorectal malignancies are still missed during colonoscopy. Several endoscopic technologies have been introduced, without radical changes. Interest in the development of artificial intelligence applications in the medical field has grown in the past decade. Artificial intelligence can help to highlight a specific region of interest that needs closer examination for the identification of polyps. The aim of this review is to report the first clinical experiences with the first US FDA-approved, real-time, deep-learning, computer-aided detection system (GI Genius™, Medtronic).
Topics: Artificial Intelligence; Colonic Polyps; Colonoscopy; Colorectal Neoplasms; Computers; Humans
PubMed: 35081745
DOI: 10.2217/fon-2021-1135