Frequent co-occurrence of high-grade dysplasia in large flat colonic polyps (>20 mm) and synchronous polyps

Endoscopic Resection of Neoplasia in the Lower GI Tract: A Clinical Algorithm

Background

Colorectal cancer is a highly prevalent malignancy and a significant driver of cancer mortality and health-related expenditure worldwide. Polyp removal reduces the incidence and mortality of colorectal cancer. In 2024, endoscopists have an array of resection modalities at their disposal. Each technique requires a unique skillset and has individual advantages and limitations. Consequently, resection in the colorectum requires an evidence-based algorithm approach that considers these factors.

Summary

A literature review of endoscopic resection for colonic neoplasia was conducted. Best supporting scientific evidence was summarized for the endoscopic resection of diminutive polyps, large ≥20 mm lesions and polyps containing invasive cancer. Factors including resection modality, complications and lesion selection were explored to inform an algorithm approach to colorectal resection.

Key Messages

Endoscopic resection in the colorectum is not a one-size-fits-all approach. Detailed understanding of polyp size, location, morphology and predicted histology are critical factors that inform appropriate endoscopic resection practice.

The Surface Morphology of Large Nonpedunculated Colonic Polyps Predicts Synchronous Large Lesions

BACKGROUND & AIMS

Large (≥20 mm) nonpedunculated colorectal polyps (LNPCPs) may have synchronous LNPCPs in up to 18% of cases. The nature of this relationship has not been investigated. We aimed to examine the relationship between individual LNPCP characteristics and synchronous colonic LNPCPs.

METHODS

Consecutive patients referred for resection of LNPCPs over 130 months until March 2022 were enrolled. Serrated lesions and mixed granularity LNPCPs were excluded from analysis. Patients with multiple LNPCPs resected were identified, and the largest was labelled as dominant. The primary outcome was the identification of individual lesion characteristics associated with the presence of synchronous LNPCPs.

RESULTS

There were 3149 of 3381 patients (93.1%) who had a single LNPCP. In 232 (6.9%) a synchronous lesion was detected. Solitary lesions had a median size of 35 mm with a predominant Paris 0-IIa morphology (42.9%) and right colon location (59.5%). In patients with ≥2 LNPCPs, the dominant lesion had a median size of 40 mm, Paris 0-IIa (47.6%) morphology, and right colon location (65.9%). In this group, 35.8% of dominant LNPCPs were non-granular compared with 18.7% in the solitary LNPCP cohort. Non-granular (NG)-LNPCPs were more likely to demonstrate synchronous disease, with left colon NG-LNPCPs demonstrating greater risk (odds ratio, 4.78; 95% confidence interval, 2.95-7.73) than right colon NG-LNPCPs (odds ratio, 1.99; 95% confidence interval, 1.39-2.86).

CONCLUSIONS

We found that 6.9% of LNPCPs have synchronous disease, with NG-LNPCPs demonstrating a greater than 4-fold increased risk. With post-colonoscopy interval cancers exceeding 5%, endoscopists must be cognizant of an individual's LNPCP phenotype when examining the colon at both index procedure and surveillance.

CLINICALTRIALS

gov, NCT01368289; NCT02000141; NCT02198729.

Does Finding Cecal Adenoma Increase the Risk of Discovering More and Advanced Adenomas in the Remainder of the Colon?

OBJECTIVES

Adenomatous polyps are common, occurring in up to 25% of the population older than 50 years of age in the United States. Conflicting data are present in the literature about the impact of specific adenoma locations and the prediction on the number and advanced histology of adenomas elsewhere. With this study we aimed to review the association between cecal adenoma and the risk of discovering more and advanced adenomas in the remainder of the colon.

METHODS

We performed a retrospective study of 1880 patients who received outpatient colonoscopies between June 2012 and December 2014 at the Veterans Affairs Medical Center in Oklahoma City. The data collected included patient demographics, indications for colonoscopy, smoking history, alcohol use, family history of colon cancer, quality of bowel preparation, number of adenomas, location, size of adenomas, and the histology of adenomas and colon cancer.

RESULTS

The mean age of the study population was 61.6 ± 9.4 year, with 95% of the population being men. Cecal adenomas were found in 243 (12.9%) of patients. Patients with cecal adenoma tended to be older (65 ± 7 vs 61 ± 10, P < 0.0001), more likely to be men (97% vs 94%, P = 0.06) and less likely to have a colonoscopy done for screening indication (11% vs. 13%., P = 0.03). After adjusting for age, sex, indication, and quality of bowel preparation, patients with cecal adenoma were found to have a sixfold increase in finding ≥10 other adenomas elsewhere (4.5% vs 0.8% P = 0.0009) and a threefold increase in finding advanced adenomas (17.7% vs 9.9% P = 0.002) in the remainder of the colon. Stratifying by location, the increased risk was more pronounced in the right side (24.7% vs 8.9% P ≤ 0.0001) compared with the left side.

CONCLUSIONS

Cecal adenoma is associated with an increased risk of finding more and advanced adenomas in the remainder of the colon, especially on the right side; therefore, the discovery of a cecal adenoma should prompt a more thorough evaluation of the entire colon, particularly the right colon.

Metachronous neoplasms in patients with laterally spreading tumours during surveillance

Background

Laterally spreading tumours represent a major challenge for endoscopic detection and resection.

Objective

To examine synchronous and metachronous neoplasms in patients with laterally spreading tumours.

Methods

We prospectively collected colonoscopy and histopathology data from patients who underwent colonoscopy in our centre at up to 6 years' follow‐up. Post‐resection surveillance outcomes between laterally spreading tumours, flat colorectal neoplasms 10 mm or greater, and large polypoid colorectal neoplasms, polypoid colorectal neoplasms 10 mm or greater, were compared.

Results

Between 2008 and 2012, 8120 patients underwent colonoscopy for symptoms (84.6%), screening (6.7%) or surveillance (8.7%). At baseline, 151 patients had adenomatous laterally spreading tumours and 566 patients had adenomatous large polypoid colorectal neoplasms. Laterally spreading tumour patients had more synchronous colorectal neoplasms than large polypoid colorectal neoplasm patients (mean 3.34 vs. 2.34, p < 0.001). Laterally spreading tumour patients significantly more often developed metachronous colorectal neoplasms (71.6% vs. 54.2%, p = 0.0498) and colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients (36.4% vs. 15.8%, p < 0.001). After correction for age and gender, laterally spreading tumour patients were more likely than large polypoid colorectal neoplasm patients to develop a colorectal neoplasm with high grade dysplasia or submucosal invasion (hazard ratio 2.9, 95% confidence interval 1.8–4.6). The risk of metachronous colorectal cancer was not significantly different in laterally spreading tumours compared to large polypoid colorectal neoplasm patients.

Conclusion

Patients with laterally spreading tumours developed more metachronous colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients. Based on these findings endoscopic treatment and surveillance recommendations for patients with laterally spreading tumours should be optimised.

Summarize the established knowledge on this subject

Laterally spreading tumours (LSTs) are a heterogeneous group of large, predominantly benign flat neoplasms that can be endoscopically treated, requiring additional time and expertise

LSTs consist of different endoscopic subtypes which are predictive of the risk of submucosal invasion (SMI)

Patients with LSTs harbour more synchronous neoplasms than patients with large polypoid colorectal neoplasms (LP‐CRNs)

What are the significant and/or new findings of this study?

Patients with LSTs more frequently have metachronous neoplasms than patients with LP‐CRNs, justifying strict surveillance

LSTs can be effectively managed by conventional endoscopic resections in most cases

Long-term follow-up after EMR of large colorectal lesions: metachronous lesions, predictors and surveillance timing

Background: Endoscopic mucosal resection (EMR) is the first-line approach to large colorectal sessile lesions. These patients have been associated with high rates of metachronous lesions (ML), but long-term follow-up (LtFU) data are lacking. We aimed at evaluating the efficacy of an LtFU protocol and analyse the development and risk factors for ML.Methods: A prospectively collected database was analysed. Seventy-six patients submitted to EMR of large colorectal sessile lesions between 2007 and 2013 complied with a specific endoscopic surveillance, consisting of two protocols - initial follow-up (iFU) and LtFU. iFU intended to inspect the mucosectomy scars twice (at 3-6 and 12 months) and remove synchronous lesions (SL). Protocol examinations of LtFU were carried out at the first- and fourth-year post-iFU, aiming to remove ML. Statistical analysis included variables related to patient, index lesion, SL and ML characteristics.Results: Rates of ML were 39.5% and 20.4% at the first- and fourth-year of LtFU, and respectively 11.8% and 3.7% of them were advanced ML. All ML were endoscopically resectable. At univariate analysis, male gender (OR: 2.91; p=.029), the presence of SL (OR 3.86, p=.010) and advanced SL (OR 4.25, p=.006) were risk factors for ML. At multivariate analysis, male gender (p=.031) and advanced SL (p=.006) were significant predictors of ML development.Conclusions: We confirmed the increased risk of ML in patients with large colorectal lesions. A significant number of advanced ML was removed at the first LtFU colonoscopy, probably it should be carried out earlier than currently recommended.

Could Mycobacterium avium subspecies paratuberculosis cause Crohn's disease, ulcerative colitis…and colorectal cancer?

Infectious agents are known causes of human cancers. Schistosoma japonicum and Schistosoma mansoni cause a percentage of colorectal cancers in countries where the respective Schistosoma species are prevalent. Colorectal cancer is a complication of ulcerative colitis and colonic Crohn’s disease, the two main forms of idiopathic inflammatory bowel disease (IIBD). Mycobacterium avium subspecies paratuberculosis (MAP), the cause of a chronic intestinal disease in domestic and wild ruminants, is one suspected cause of IIBD. MAP may therefore be involved in the pathogenesis of IIBD-associated colorectal cancer as well as colorectal cancer in individuals without IIBD (sporadic colorectal cancer) in countries where MAP infection of domestic livestock is prevalent and MAP’s presence in soil and water is extensive. MAP organisms have been identified in the intestines of patients with sporadic colorectal cancer and IIBD when high magnification, oil immersion light microscopy (×1000 total magnification rather than the usual ×400 total magnification) is used. Research has demonstrated MAP’s ability to invade intestinal goblet cells and cause acute and chronic goblet cell hyperplasia. Goblet cell hyperplasia is the little-recognized initial pathologic lesion of sporadic colorectal cancer, referred to as transitional mucosa, aberrant crypt foci, goblet cell hyperplastic polyps or transitional polyps. It is the even lesser-recognized initial pathologic feature of IIBD, referred to as hypermucinous mucosa, hyperplastic-like mucosal change, serrated epithelial changes, flat serrated changes, goblet cell rich mucosa or epithelial hyperplasia. Goblet cell hyperplasia is the precursor lesion of adenomas and dysplasia in the classical colorectal cancer pathway, of sessile serrated adenomas and serrated dysplasia in the serrated colorectal cancer pathway, and of flat and elevated dysplasia and dysplasia-associated lesions or masses in IIBD-associated intestinal cancers. MAP’s invasion of intestinal goblet cells may result in the initial pathologic lesion of IIBD and sporadic colorectal cancer. MAP’s persistence in infected intestines may result in the eventual development of both IIBD-associated and sporadic colorectal cancer.

Multiple behavioral factors are associated with occurrence of large, flat colorectal polyps

PURPOSE

The prevalence of advanced dysplasia and synchronous lesions is particularly high in patients with large, flat colorectal polyps. However, the impact of lifestyle on the development of such polyps is poorly investigated. Hence, this study aims to identify associations between behavioral factors and the occurrence of large, flat colorectal polyps.

METHODS

Behavioral factors were retrospectively analyzed in patients with large, flat polyps and control patients with at most one diminutive polyp. Information on lifestyle factors, comorbidities, and demographic parameters were determined by a structured, self-administered questionnaire.

RESULTS

Questionnaires of 350 patients with large, flat polyps and 489 control patients were included in the analysis. Most large, flat colorectal polyps contained adenoma with low-grade neoplasia and were located in the right colon. Multivariate analysis showed that advanced age (per 1-year increase-OR 1.09, CI 1.07-1.11, p < 0.0001), frequent cigarette smoking (OR 2.04, CI 1.25-3.32, p = 0.0041), daily consumption of red meat (OR 3.61, CI 1.00-12.96, p = 0.0492), and frequent bowel movements (OR 1.62, CI 1.13-2.33, p = 0.0093) were independent risk factors for occurrence of large, flat colorectal polyps. In contrast, frequent intake of cereals (OR 0.62, CI 0.44-0.88, p = 0.0074) was associated with a reduced risk.

CONCLUSION

Multiple behavioral factors modulate the risk for developing large, flat colorectal polyps. This knowledge can be used to improve prevention of colorectal cancer.

High yield of synchronous lesions in referred patients with large lateral spreading colorectal tumors

BACKGROUND AND AIMS

There are few data on the prevalence of synchronous colorectal lesions in patients who have large lateral spreading tumors (LLSTs). We sought to describe the rate of synchronous lesions found in patients who underwent endoscopic resection of large sessile adenomas and serrated lesions.

METHODS

This is a retrospective assessment of a prospectively created database of 728 consecutive patients with resected LLSTs who underwent complete clearing of the colon during 2 colonoscopies by a single expert endoscopist.

RESULTS

The 728 patients with resected LLSTs and complete clearing had 4578 synchronous lesions, including 584 patients (80.2%) with at least 1 synchronous conventional adenoma, 132 (18.1%) with at least 1 synchronous conventional adenoma ≥ 20 mm in size, 294 (40.4%) with at least 1 synchronous advanced conventional adenoma, and 6 patients with a synchronous lesion with cancer. Patients with an index large sessile conventional adenoma compared with those with an index large serrated lesion had on average more synchronous conventional adenomas (4.8 vs 2.9, P = .001) and fewer synchronous serrated lesions (1.4 vs 4.5, P < .001). Of the 97 patients with a serrated class index lesion, 28 (28.9%) met criteria for serrated polyposis.

CONCLUSIONS

There is a very high prevalence of synchronous lesions, including other large and advanced synchronous lesions, in patients with flat or sessile conventional adenomas and serrated colorectal polyps. Patients with LLSTs in the colon need detailed clearing of the rest of the colon. Patients referred for endoscopic resection of serrated lesions ≥ 20 mm have a very high prevalence of serrated polyposis. This study has potential implications for further stratification of high-risk patient groups in postpolypectomy surveillance guidelines.