Long-term Risk of Colorectal Cancer After Removal of Conventional Adenomas and Serrated Polyps

Increased Risk of Colorectal Cancer Tied to Advanced Colorectal Polyps: An Untapped Opportunity to Screen First-Degree Relatives and Decrease Cancer Burden

Advanced adenomas represent a subset of colorectal polyps that are known to confer an increased risk of colorectal neoplasia to the affected individual and their first-degree relatives (FDRs). Accordingly, professional guidelines suggest earlier and more intensive screening for FDRs of those with advanced adenomas similar to FDRs of those with colorectal cancer (CRC). Although the risk to family members is less clear among patients with advanced serrated polyps, they are often considered in the same category. Unfortunately, there is a growing concern that patients, endoscopists, and primary care providers are unaware of the familial risk associated with these polyps, leaving a wide gap in screening these high-risk individuals. Herein, we propose a standardized language around advanced colorectal polyps and present a detailed review of the literature on associated familial risk. We outline the challenges to implementing the current screening recommendations and suggest approaches to overcome these limitations, including a proposed new colonoscopy quality metric to capture communication of familial CRC risk. Improving screening in these high-risk groups has the potential to substantially reduce the burden of CRC.

Computed Tomography Colonography Versus Standard Optical Colonoscopy for the Detection of Colorectal Polyp in Patients Who Faced Curative Surgery for Colorectal Cancer: A Diagnostic Performance Study

Data regarding computed tomography colonography, standard optical colonoscopy, and enhanced colonoscopy/histopathology at 1-year after surgery and at 6-month intervals for the next 2 years of 345 patients who faced curative surgery for colorectal cancer were included in this analysis. Computed tomography colonography and standard optical colonoscopy both detected 298 polyps as suspicious. With reference to enhanced colonoscopy/histopathology, sensitivities for the detection of any polyps for computed tomography colonography and standard optical colonoscopy were 0.952 and 0.906, while, accuracies were 0.783 and 0.641, respectively. Computed tomography colonography may be a sensitive and accurate surveillance tool for colorectal cancer patients.

Risk of colorectal cancer incidence and mortality after polypectomy: a Swedish record-linkage study

BACKGROUND

Long-term colorectal cancer incidence and mortality after colorectal polyp removal remains unclear. We aimed to assess colorectal cancer incidence and mortality in individuals with removal of different histological subtypes of polyps relative to the general population.

METHODS

We did a matched cohort study through prospective record linkage in Sweden in patients aged at least 18 years with a first diagnosis of colorectal polyps in the nationwide gastrointestinal ESPRESSO histopathology cohort (1993-2016). For each polyp case, we identified up to five matched reference individuals from the Total Population Register on the basis of birth year, age, sex, calendar year of biopsy, and county of residence. We excluded patients and reference individuals with a diagnosis of colorectal cancer either before or within the first 6 months after diagnosis of the index polyp. Polyps were classified by morphology codes into hyperplastic polyps, sessile serrated polyps, tubular adenomas, tubulovillous adenomas, and villous adenomas. Colorectal cancer cases were identified from the Swedish Cancer Registry, and cause-of-death data were retrieved from the Cause of Death Register. We collected information about the use of endoscopic examination before and after the index biopsy from the Swedish National Patient Registry, and counted the number of endoscopies done before and after the index biopsies. We calculated cumulative risk of colorectal cancer incidence and mortality at 3, 5, 10, and 15 years, and computed hazard ratios (HRs) and 95% CIs for colorectal cancer incidence and mortality using a stratified Cox proportional hazards model within each of the matched pairs.

FINDINGS

178 377 patients with colorectal polyps and 864 831 matched reference individuals from the general population were included in our study. The mean age of patients at polyp diagnosis was 58·6 (SD 13·9) years for hyperplastic polyps, 59·7 (14·2) years for sessile serrated polyps, 63·9 (12·9) years for tubular adenomas, 67·1 (12·1) years for tubulovillous adenomas, and 68·9 (11·8) years for villous adenomas. During a median of 6·6 years (IQR 3·0-11·6) of follow-up, we documented 4278 incident colorectal cancers and 1269 colorectal cancer-related deaths in patients with a polyp, and 14 350 incident colorectal cancers and 5242 colorectal cancer deaths in general reference individuals. The 10-year cumulative incidence of colorectal cancer was 1·6% (95% CI 1·5-1·7) for hyperplastic polyps, 2·5% (1·9-3·3) for sessile serrated polyps, 2·7% (2·5-2·9) for tubular adenomas, 5·1% (4·8-5·4) for tubulovillous adenomas, and 8·6% (7·4-10·1) for villous adenomas compared with 2·1% (2·0-2·1) in reference individuals. Compared with reference individuals, patients with any polyps had an increased risk of colorectal cancer, with multivariable HR of 1·11 (95% CI 1·02-1·22) for hyperplastic polyps, 1·77 (1·34-2·34) for sessile serrated polyps, 1·41 (1·30-1·52) for tubular adenomas, 2·56 (2·36-2·78) for tubulovillous adenomas, and 3·82 (3·07-4·76) for villous adenomas (p<0·05 for all polyp subtypes). There was a higher proportion of incident proximal colon cancer in patients with serrated (hyperplastic and sessile) polyps (52-57%) than in those with conventional (tubular, tubulovillous, and villous) adenomas (30-46%). For colorectal cancer mortality, a positive association was found for sessile serrated polyps (HR 1·74, 95% CI 1·08-2·79), tubulovillous adenomas (1·95, 1·69-2·24), and villous adenomas (3·45, 2·40-4·95), but not for hyperplastic polyps (0·90, 0·76-1·06) or tubular adenomas (0·97, 0·84-1·12).

INTERPRETATION

In a largely screening-naive population, compared with individuals from the general population, patients with any polyps had a higher colorectal cancer incidence, and those with sessile serrated polyps, tubulovillous adenomas, and villous adenomas had a higher colorectal cancer mortality.

FUNDING

US National Institutes of Health, American Cancer Society, American Gastroenterological Association, Union for International Cancer Control.

The Coexistence of Colorectal Polyps in the Right Colon Increases the Malignant Risk of Laterally Spreading Tumors

Background

The coexistence of colorectal polyps with laterally spreading tumors (LSTs) is commonly observed during colonoscopy. However, there are rare studies that assess the malignant risks for LSTs with colorectal polyps, which might largely contribute to further strategies of treatment and follow-up plans in LSTs.

Methods

We conducted a retrospective cohort study that enrolled 206 patients with LSTs in the Endoscopy Center and Endoscopy Research Institute, Renji Hospital, Shanghai Jiao Tong University, China. The subjects with LSTs were divided into two groups: the nonpolyp group with 89 patients and the polyp group with 117 patients. Binary logistic regression was used to identify the independent predictors of outcomes of interest.

Results

The risk of the polyps' coexistence phenomenon increased in males compared with females (OR = 2.138, p = 0.047), especially in those between 50 and 75 years old (OR = 7.074, p = 0.036). Tumor size (3–4 cm), LSTs with tubulovillous types, and history of polyps statistically increased the risk of the polyp coexistence phenomenon (OR = 5.768, p = 0.003; OR = 36.345, p = 0.024; OR = 13.245, p < 0.0001, respectively). LST-NG-PD (OR = 20.982, p = 0.017) and LSTs ≥ 5 cm (OR = 37.604, p = 0.038) notably increased the malignant risk of LSTs. When the simultaneous polyps are located in the right colon, the risk of malignant LSTs (OR = 58.540, p = 0.013) positively increased.

Conclusion

The simultaneous colorectal polyps in the right colon were the most important risk factor to predict the malignant risk of LSTs.

Body fatness over the life course and risk of serrated polyps and conventional adenomas

Serrated polyps (SPs) and conventional adenomas represent 2 distinct groups of colorectal premalignancy. The influence of early life adiposity on risk of these precursors remains unclear. Within the Nurses' Health Study, the Nurses' Health Study 2, and the Health Professionals Follow-up Study, we assessed body fatness during childhood using 9-level somatotype and obtained weight and body mass index (BMI) in adulthood. We used multivariable-adjusted logistic regression to examine the association of SPs and conventional adenomas with body fatness in early childhood (age 5), late childhood (age 10), early adulthood (age 18/21) and middle adulthood (baseline) and weight change during early-to-middle adulthood. During 18-20 years of follow-up, we documented 8,697 SPs and 10,219 conventional adenomas in 132,514 women; 2,403 SPs and 4,495 conventional adenomas in 29,207 men. We found a modest positive association of adiposity in early and late childhood with risk of SPs and conventional adenomas, with odds ratios ranging from 1.12 to 1.18 for comparison of extreme somatotypes groups. The associations were attenuated after adjusting for adulthood BMI but remained significant for conventional adenomas. No association with early life body fatness was found in men. Adulthood body fatness and weight change during early-to-middle adulthood showed positive relationships with SPs and conventional adenomas in both women and men, with stronger associations observed for SPs (p_{heterogeneity}  < 0.0001). Our findings indicated a potential role in development of colorectal cancer precursors of childhood body fatness in women, and early-to-middle adulthood weight gain and attained adiposity in both sexes.

Polyp Detection Rate as a Surrogate for Adenoma and Sessile Serrated Adenoma/Polyp Detection Rates

Introduction

Quality measures for colonoscopy such as adenoma detection rate (ADR) have been proposed to be surveilled for ensuring minimum standards. However, its direct measurement is time consuming and often neglected. Extrapolating ADR and other quality measures from polyp detection rate (PDR) can be a pragmatic alternative.

Objective

To determine quotients for estimating ADR and sessile serrated adenoma/polyp detection rate (SSA/P-DR) from PDR in an Australian cohort.

Methods

Consecutive adult patient colonoscopies during a 1-year period were retrospectively assessed in a single Australian tertiary endoscopy center. Adenoma detection quotient (ADQ) and SSA/P detection quotient (SSA/P-DQ) were defined as the division of ADR and SSA/P-DR by PDR, respectively. The primary outcome was the number of procedures to achieve a stable cumulative ADQ and SSA/P-DQ. Secondary outcomes included evaluation of ADQ and SSA/P-DQ in different subsets.

Results

In total, 2,657 colonoscopies were performed by 15 endoscopists in 2016. The ADR, SSA/P-DR, and PDR found were 32.2, 6.7, and 47.3%, respectively. The ADQ and SSA/P-DQ values found were 0.68 and 0.14, respectively. After approximately 500 procedures, both ADQ and SSA/P-DQ became stable. Interclass correlation coefficient (ICC) for the prediction of ADR from ADQ was excellent for all endoscopists that performed >177 procedures in that year (ICC 0.84).

Conclusions

ADQ and SSA/P-DQ values were consistent when over 500 procedures were analyzed. ADQ had an excellent correlation with ADR when >177 procedures per endoscopist were evaluated.

British Society of Gastroenterology/Association of Coloproctology of Great Britain and Ireland/Public Health England post-polypectomy and post-colorectal cancer resection surveillance guidelines

These consensus guidelines were jointly commissioned by the British Society of Gastroenterology (BSG), the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and Public Health England (PHE). They provide an evidence-based framework for the use of surveillance colonoscopy and non-colonoscopic colorectal imaging in people aged 18 years and over. They are the first guidelines that take into account the introduction of national bowel cancer screening. For the first time, they also incorporate surveillance of patients following resection of either adenomatous or serrated polyps and also post-colorectal cancer resection. They are primarily aimed at healthcare professionals, and aim to address:Which patients should commence surveillance post-polypectomy and post-cancer resection?What is the appropriate surveillance interval?When can surveillance be stopped? two or more premalignant polyps including at least one advanced colorectal polyp (defined as a serrated polyp of at least 10 mm in size or containing any grade of dysplasia, or an adenoma of at least 10 mm in size or containing high-grade dysplasia); or five or more premalignant polyps The Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument provided a methodological framework for the guidelines. The BSG's guideline development process was used, which is National Institute for Health and Care Excellence (NICE) compliant.two or more premalignant polyps including at least one advanced colorectal polyp (defined as a serrated polyp of at least 10 mm in size or containing any grade of dysplasia, or an adenoma of at least 10 mm in size or containing high-grade dysplasia); or five or more premalignant polyps The key recommendations are that the high-risk criteria for future colorectal cancer (CRC) following polypectomy comprise either:two or more premalignant polyps including at least one advanced colorectal polyp (defined as a serrated polyp of at least 10 mm in size or containing any grade of dysplasia, or an adenoma of at least 10 mm in size or containing high-grade dysplasia); or five or more premalignant polyps This cohort should undergo a one-off surveillance colonoscopy at 3 years. Post-CRC resection patients should undergo a 1 year clearance colonoscopy, then a surveillance colonoscopy after 3 more years.

Epidemiology and risk factors of colorectal cancer in China

In China, colorectal cancer (CRC) ranked fourth and fifth in the highest incidence and mortality rates of all malignancies in 2018, respectively. Although these rates are below the world average, China placed first worldwide in the number of new CRC cases and CRC-related deaths because of its comparatively large population. This disease represents a threat to the health of population and incurs a heavy economic burden on the society and individuals. CRC has various risk factors, including age, sex, lifestyle, genetic factors, obesity, diabetes, gut microbiota status, and precancerous lesions. Furthermore, incidence and mortality rates of CRC are closely related to socioeconomic development levels, varying according to regional and population characteristics. Prevention is the main strategy to reduce incidence and mortality rates of CRC. This can be achieved through strategies stimulating lifestyle changes, healthy diet habits, and early screening for high-risk individuals. To reduce the burden of CRC, public health officials should promote prevention and management of modifiable risk factors through national policies. The rising incidence and mortality rates of CRC in China may be timely curbed by clarifying specific epidemiological characteristics, optimizing early screening strategies, and strictly implementing diagnosis and treatment guidelines. Thus, this study aimed to collect and report the current research status on epidemiology and risk factors of CRC in China.

Variation in post-colonoscopy colorectal cancer across colonoscopy providers in English National Health Service: population based cohort study

OBJECTIVES

To quantify post-colonoscopy colorectal cancer (PCCRC) rates in England by using recent World Endoscopy Organisation guidelines, compare incidence among colonoscopy providers, and explore associated factors that could benefit from quality improvement initiatives.

DESIGN

Population based cohort study.

SETTING

National Health Service in England between 2005 and 2013.

POPULATION

All people undergoing colonoscopy and subsequently diagnosed as having colorectal cancer up to three years after their investigation (PCCRC-3yr).

MAIN OUTCOME MEASURES

National trends in incidence of PCCRC (within 6-36 months of colonoscopy), univariable and multivariable analyses to explore factors associated with occurrence, and funnel plots to measure variation among providers.

RESULTS

The overall unadjusted PCCRC-3yr rate was 7.4% (9317/126 152), which decreased from 9.0% in 2005 to 6.5% in 2013 (P<0.01). Rates were lower for colonoscopies performed under the NHS bowel cancer screening programme (593/16 640, 3.6%), while they were higher for those conducted by non-NHS providers (187/2009, 9.3%). Rates were higher in women, in older age groups, and in people with inflammatory bowel disease or diverticular disease, in those with higher comorbidity scores, and in people with previous cancers. Substantial variation in rates among colonoscopy providers remained after adjustment for case mix.

CONCLUSIONS

Wide variation exists in PCCRC-3yr rates across NHS colonoscopy providers in England. The lowest incidence was seen in colonoscopies performed under the NHS bowel cancer screening programme. Quality improvement initiatives are needed to address this variation in rates and prevent colorectal cancer by enabling earlier diagnosis, removing premalignant polyps, and therefore improving outcomes.