New polyps, old tricks: controversy about removing benign bowel lesions

Management of Serrated Polyps of the Colon

PURPOSE OF REVIEW

The purpose of this review is to summarize the management of serrated colorectal polyps (SPs), with a particular focus on the most common premalignant SP, sessile serrated adenoma or polyp (SSA/P). These lesions present a challenge for endoscopists with respect to detection and resection, and are also susceptible to pathologic misdiagnosis.

RECENT FINDINGS

Patients with SSA/Ps are at an increased risk of future colorectal neoplasia, including advanced polyps and cancer. Reasonable benchmarks for SP detection rates are 5-7% for SSA/Ps and 10-12% for proximal SPs. Certain endoscopic techniques such as chromoendoscopy, narrow band imaging, water immersion, and wide-angle viewing may improve SSA/P detection. Emerging endoscopic techniques such as underwater polypectomy, suction pseudopolyp technique, and piecemeal cold snare polypectomy are helpful tools for the endoscopist's armamentarium for removing SSA/Ps. Proper orientation of SSA/P specimens can improve the accuracy of pathology readings. Patients with confirmed SSA/Ps and proximal HPs should undergo surveillance at intervals similar to what is recommended for patients with conventional adenomas. Patients with SSA/Ps may also be able to lower their risk of future polyps by targeting modifiable risk factors including tobacco and alcohol use and high-fat diets. NSAIDs and aspirin appear to be protective agents. SPs and SSA/Ps in particular are important colorectal cancer precursors that merit special attention to ensure adequate detection, resection, and surveillance.

British Society of Gastroenterology position statement on serrated polyps in the colon and rectum

Serrated polyps have been recognised in the last decade as important premalignant lesions accounting for between 15% and 30% of colorectal cancers. There is therefore a clinical need for guidance on how to manage these lesions; however, the evidence base is limited. A working group was commission by the British Society of Gastroenterology (BSG) Endoscopy section to review the available evidence and develop a position statement to provide clinical guidance until the evidence becomes available to support a formal guideline. The scope of the position statement was wide-ranging and included: evidence that serrated lesions have premalignant potential; detection and resection of serrated lesions; surveillance strategies after detection of serrated lesions; special situations-serrated polyposis syndrome (including surgery) and serrated lesions in colitis; education, audit and benchmarks and research questions. Statements on these issues were proposed where the evidence was deemed sufficient, and re-evaluated modified via a Delphi process until >80% agreement was reached. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool was used to assess the strength of evidence and strength of recommendation for finalised statements. Key recommendation: we suggest that until further evidence on the efficacy or otherwise of surveillance are published, patients with sessile serrated lesions (SSLs) that appear associated with a higher risk of future neoplasia or colorectal cancer (SSLs ≥10 mm or serrated lesions harbouring dysplasia including traditional serrated adenomas) should be offered a one-off colonoscopic surveillance examination at 3 years (weak recommendation, low quality evidence, 90% agreement).

Gastrointestinal cancer screening: screening may release new research funding to improve health service also in routine clinics

We are far from having seen the ideal method of screening for colorectal cancer (CRC) and the downsides of screening have not been fully addressed. Funding of adequately sized screening trials with a 10-15-year perspective for endpoints CRC mortality and incidence is difficult to get. Also, with such time horizons, there will always be an ongoing study to be awaited before feeling obliged to invest in the next. New, promising screening methods may, however, emerge far more often than every 10th year, and the knowledge gap may easily widen unless research is made a key responsibility for any ongoing cancer screening program. Previous lost battles on screening research may be won if accepting that scientific evidence may be obtained within the framework of screening programs - provided that they are designed as platforms for Comparative Effectiveness Research (CER). Accepting that CER-based screening programs should be preferred to non-CER programs and seriously compete for their funding sources, then CER screening programs may not be considered so much as contenders for ordinary clinical research funds. Also, CER within a screening framework may benefit patients in routine clinics as shown by screening research in Nordic countries. The Nordic countries have been early contributors to research on CRC screening, but slow in implementing screening programs.

Long-term risk of colorectal cancer in individuals with serrated polyps

OBJECTIVE

Although serrated polyps may be precursors of colorectal cancer (CRC), prospective data on the long-term CRC risk in individuals with serrated polyps are lacking.

DESIGN

In a population-based randomised trial, 12,955 individuals aged 50-64 years were screened with flexible sigmoidoscopy, while 78 220 individuals comprised the control arm. We used Cox models to estimate HRs with 95% CIs for CRC among individuals with ≥1 large serrated polyp (≥10 mm in diameter), compared with individuals with adenomas at screening, and to population controls, and multivariate logistic regression to assess polyp risk factors for CRC.

RESULTS

A total of 103 individuals had large serrated polyps, of which 81 were included in the analyses. Non-advanced adenomas were found in 1488 individuals, advanced adenomas in 701. Median follow-up was 10.9 years. Compared with the control arm, the HR for CRC was 2.5 (95% CI 0.8 to 7.8) in individuals with large serrated polyps, 2.0 (95% CI 1.3 to 2.9) in individuals with advanced adenomas and 0.6 (95% CI 0.4 to 1.1) in individuals with non-advanced adenomas. A large serrated polyp was an independent risk factor for CRC, adjusted for histology, size and multiplicity of concomitant adenomas (OR 3.3; 95% CI 1.3 to 8.6). Twenty-three large serrated polyps found at screening were left in situ for a median of 11.0 years. None developed into a malignant tumour.

CONCLUSIONS

Individuals with large serrated polyps have an increased risk of CRC, comparable with individuals with advanced adenomas. However, this risk may not be related to malignant growth of the serrated polyp.

TRIAL REGISTRATION NUMBER

The Norwegian Colorectal Cancer Screening trial is registered at clinicaltrials.gov (NCT00119912).

[Equality in clinical practice. Proposals for patients, professionals and managers and policies to limit discrimination]

OBJECTIVE

To make feasible and practical proposals to improve equality in the course of clinical care during the patient-provider encounter.

METHODS

Design: A focus group study was conducted with a qualitative approach from the perspective of reducing health inequalities in the clinic. Setting: A classroom discussion focused on equality in clinical work. Subjects: 98 professionals from several countries. Measurement tools: An analysis of the responses was performed, grouped by themes interpreted by analysts, and restructured to provide consistency and uniformity to responses given. Data were collected using a questionnaire with open answers, allowing free-form answers to three general questions that addressed improving equality from the perspective of the professional themselves, patients, and health policy managers. No saturation horizon of analytical discourses was set, to understand that from this subjective prioritization of opinion there is no possibility that discourses reached saturation.

RESULTS

Responses were added to the 3 principal axes, recommending that professionals be aware of their discriminatory ability. Patients were asked to trust their health professionals and that they should be assigned to a professional. It was also proposed that managers provide information systems, help reduce health inequalities, and encourage professional freedom.

CONCLUSIONS

The paper presents concrete measures to promote improved equality in clinics during the delivery of health care.

Colorectal neoplasia pathways: state of the art

Colorectal cancer (CRC) is a heterogeneous disease and each CRC possesses a unique molecular tumor profile. The main pathways of oncogenesis are the chromosomal instability, microsatellite instability and serrated neoplasia pathway. Sessile serrated adenomas/polyps (SSA/Ps) may be the precursor lesions of CRC arising via the serrated neoplasia pathway. This has led to a paradigm shift because all SSA/Ps should be detected and resected during colonoscopy. The ability to accurately detect and resect only those polyps with a malignant potential could result in safer and cost-effective practice. Optimization of the endoscopic classification systems is however needed to implement targeted prevention methods.

Sessile serrated adenomas: an evidence-based guide to management

The concept of serrated colorectal neoplasia and a serrated pathway to colorectal cancer (CRC) is relatively new and continuing to evolve, but it has become highly relevant to gastroenterologists, pathologist, and oncologists alike. Sessile serrated adenomas (SSA) are now thought to be the major precursor lesion of serrated pathway cancers, which represent up to one-third of all sporadic CRC cases. However, despite their increasingly recognized importance, relatively little is known about the epidemiology and natural history of SSAs, and the molecular and epigenetic aspects are incompletely understood. Endoscopists must be aware of the unique features of SSAs so that the practice of colonoscopic screening for CRC can include optimized detection, removal, and appropriate surveillance of SSAs and other serrated precursor lesions. In this review, we discuss the history, epidemiology, and pathologic aspects of SSAs, as well as a recommended management approach and a discussion of uncertainties and opportunities for future research.

Serrated neoplasia of the colon: what do we really know?

Colonoscopy offers incomplete protection from colorectal cancer, particularly in the right colon. Part of this inadequacy may be related to serrated neoplasia. Serrated polyps of the colorectum are now understood to be a heterogeneous group of polyps, some of which are cancer precursors, such as the sessile serrated adenoma (SSA) and the traditional serrated adenoma (TSA). In contrast to conventional adenomas, there is limited published literature on the epidemiology and natural history of these lesions. Furthermore, existing guidelines regarding screening and surveillance practices for these polyps are based largely on expert opinion without firm evidence. In this review, we describe the current understanding of the molecular biology, histopathology, and endoscopic features of serrated neoplasia of the colorectum, with an emphasis on aspects relevant to the practicing gastroenterologist.

Colorectal cancer: consensus for CRC screening, but who addresses the controversies?

In an update on recommendations for colorectal cancer screening, an Asia–Pacific consensus group has set a good standard for presenting level of agreement to recommendation levels. However, this update also exposes how consensus groups might concentrate on the less controversial issues—leaving the tricky questions in the dark.