Significant Polyps Research Articles

Surgeon assessment of significant rectal polyps using white light endoscopy alone and in comparison to fluorescence-augmented AI lesion classification

PurposePerioperative decision making for large (> 2 cm) rectal polyps with ambiguous features is complex. The most common intraprocedural assessment is clinician judgement alone while radiological and endoscopic biopsy can provide periprocedural detail. Fluorescence-augmented machine learning (FA-ML) methods may optimise local treatment strategy.MethodsSurgeons of varying grades, all performing colonoscopies independently, were asked to visually judge endoscopic videos of large benign and early-stage malignant (potentially suitable for local excision) rectal lesions on an interactive video platform (Mindstamp) with results compared with and between final pathology, radiology and a novel FA-ML classifier. Statistical analyses of data used Fleiss Multi-rater Kappa scoring, Spearman Coefficient and Frequency tables.ResultsThirty-two surgeons judged 14 ambiguous polyp videos (7 benign, 7 malignant). In all cancers, initial endoscopic biopsy had yielded false-negative results. Five of each lesion type had had a pre-excision MRI with a 60% false-positive malignancy prediction in benign lesions and a 60% over-staging and 40% equivocal rate in cancers. Average clinical visual cancer judgement accuracy was 49% (with only ‘fair’ inter-rater agreement), many reporting uncertainty and higher reported decision confidence did not correspond to higher accuracy. This compared to 86% ML accuracy. Size was misjudged visually by a mean of 20% with polyp size underestimated in 4/6 and overestimated in 2/6. Subjective narratives regarding decision-making requested for 7/14 lesions revealed wide rationale variation between participants.ConclusionCurrent available clinical means of ambiguous rectal lesion assessment is suboptimal with wide inter-observer variation. Fluorescence based AI augmentation may advance this field via objective, explainable ML methods.

Twenty First Century Technological Toolbox Innovation for Transanal Minimally Invasive Surgery (TAMIS).

Transanal minimally invasive surgery (TAMIS) is an effective procedure that plays an important role in the care of patients with significant rectal neoplasia and polyps including early-stage cancers. However, it is perhaps underutilised and under threat from both advanced flexible endoscopic procedures and proceduralists (who often act as gatekeepers for referral to colorectal surgeons), as well as from robotic surgery proponents. TAMIS advocates can learn and adopt practice insights from both these fields and incorporate available technological innovations building on the huge accomplishments already delivered in this area. Evolved practice through technology has the potential to offset current limitations regarding technical constraints and indeed patient selection (via artificial intelligence methods). Potential target areas for advances are considered in this review from different perspectives: (1) Access (2) Insufflation (3) Visualisation (4) Disease Characterization in situ, and (5) Tissue Handling and Suturing. While a bundle approach may be most useful, the advances for each component are potentially useful in their own right and could be applied without depending on the other practices detailed so that more accurate (and perhaps even numerically more) TAMIS procedures can be performed globally to improve patient care.

Association of Endoscopist Colonoscopy Quality Measures With Follow-Up Colonoscopy Outcomes After Positive Stool Tests (Multitarget Stool DNA or Fecal Immunochemical Test): Retrospective Cross-Sectional Analysis of Data From the New Hampshire Colonoscopy Registry.

Negative colonoscopies following positive stool tests could result from stool test characteristics or from the quality of endoscopist performance. We used New Hampshire Colonoscopy Registry data to examine the association between endoscopist detection rates and polyp yield in colonoscopies performed for positive fecal immunochemical test (FIT) or multitarget stool DNA (mt-sDNA) test to evaluate the degree to which positive stool tests followed by negative colonoscopy ("false positives") vary with endoscopist quality. In addition, we investigated the frequency of significant polyps in the subgroup of highest quality colonoscopies following positive stool tests. We compared the frequencies of negative colonoscopies and of specific polyps following positive stool tests across quartiles of endoscopist adenoma detection rate (ADR) and clinically significant serrated polyp detection rate (CSSDR). Our sample included 864 mt-sDNA+ and 497 FIT+ patients. We found a significantly lower frequency of negative colonoscopies following positive stool tests among endoscopists with higher ADR and CSSDR, particularly in the 2 highest quartiles. In addition, detection of any adenoma after a positive stool test for endoscopists in the fourth ADR quartile was 63.3% (FIT+) and 62.8% (mt-sDNA+). Among endoscopists in the fourth CSSDR quartile, sessile serrated lesions were found in 29.2% of examinations following a positive mt-sDNA and in 13.5% following FIT+ examinations. The frequency of negative colonoscopies after positive stool tests was significantly higher in examinations performed by endoscopists with low ADR and CSSDR. Our results also suggest a benchmark target of at least 40% for ADR in patients with mt-sDNA+ or FIT+ tests and 20% for sessile serrated lesions in mt-sDNA+ patients.

Substratifying the risk of covert malignancy in significant rectal polyps: Outcomes from a specialist multidisciplinary team (MDT).

A treatment strategy for patients with a significant polyp or early colon cancer (SPECC) of the rectum presents a challenge due to the significant rate of covert malignancy and lack of standardized assessment. For this reason, NICE recommends multidisciplinary meetings to improve outcomes. The primary aim of the present study was to report the performance of our specialist early rectal cancer (SERC) multidisciplinary team (MDT) in correctly substratifying the risk of cancer and to discuss the limitations of staging investigations in those patients with "poor outcomes". This was a retrospective review of patients referred to our SERC MDT from 2014 to 2019. Lesions were assigned by the MDT to three pre-resection categories (low, intermediate, high) according to the risk of covert malignancy. Resection method and final histology were compared to the pre-resection categories. Of 350 SPECC lesions, 174 were assessed as low-risk, 108 intermediate-risk and 68 high-risk. The cancer incidence was 4.8%, 8.3% and 53%, respectively (15.5% overall). Eight lesions were categorized as low-risk but following piecemeal resection were found to be malignant. Five lesions, three of which were categorized as high-risk, were ultimately benign following conventional surgery. One pT1sm1 cancer, removed by anterior resection, may have been treated by local excision. A total of 83% of malignant polyps were triaged to an en bloc resection technique and surgical resection avoided for nearly all benign lesions. However, 12 patients from this cohort were deemed to have a poor outcome because of miscategorization. Further comparative research is needed to establish the optimum strategy for rectal SPECC lesion assessment. There is currently no consensus for staging significant polyps of the rectum. This paper reports the effectiveness of a specialist early rectal cancer MDT to correctly risk-stratify significant rectal polyps. It underscores the importance of accurate categorization for treatment decision-making, while acknowledging the limitations of current staging modalities.

Prevalence and predictive factors of colorectal sessile serrated lesions in younger individuals.

Sessile serrated lesions (SSLs) are obscured lesions predominantly in the right-sided colon and associated with interval colorectal cancer; however, their prevalence and risk factors among younger individuals remain unclear. This retrospective study enrolled individuals who underwent index colonoscopy. The primary outcome was the SSL prevalence in the younger (<50 years) and older (≥50 years) age groups, while the secondary outcomes included clinically significant serrated polyps (CSSPs). Multivariable logistic regression was employed to identify predictors. Of the 9854 eligible individuals, 4712 (47.8%) were categorized into the younger age group. Individuals in the younger age group exhibited lower prevalences of adenomas (22.6% vs. 46.2%; P<0.001) and right-sided adenomas (11.2% vs. 27.2%; P<0.001) compared with their older counterparts. However, both groups exhibited a similar prevalence of SSLs (7.2% vs. 6.5%; P=0.16) and CSSPs (10.3% vs. 10.3%;P=0.96). Multivariable analysis revealed that age 40-49 years (odds ratio [OR] 1.81, 95%CI 1.01-3.23), longer withdrawal time (OR 1.17, 95%CI 1.14-1.20, per minute increment), and endoscopist performance (OR 3.35, 95%CI 2.44-4.58) were independent predictors of SSL detection in the younger age group. No significant correlation was observed between adenoma and SSL detection rates among endoscopists. SSLs are not uncommon among younger individuals. Moreover, diligent effort and expertise are of paramount importance in SSL detection. Future studies should explore the clinical significance of SSLs in individuals of younger age.

CLASSICA: Validating artificial intelligence in classifying cancer in real time during surgery.

Treatment pathways for significant rectal polyps differ depending on the underlying pathology, but pre-excision profiling is imperfect. It has been demonstrated that differences in fluorescence perfusion signals following injection of indocyanine green (ICG) can be analysed mathematically and, with the assistance of artificial intelligence (AI), used to classify tumours endoscopically as benign or malignant. This study aims to validate this method of characterization across multiple clinical sites regarding its generalizability, usability and accuracy while developing clinical-grade software to enable it to become a useful method. The CLASSICA study is a prospective, unblinded multicentre European observational study aimed to validate the use of AI analysis of ICG fluorescence for intra-operative tissue characterization. Six hundred patients undergoing transanal endoscopic evaluation of significant rectal polyps and tumours will be enrolled in at least five clinical sites across the European Union over a 4-year period. Video recordings will be analysed regarding dynamic fluorescence patterns centrally as software is developed to enable analysis with automatic classification to happen locally. AI-based classification and subsequently guided intervention will be compared with the current standard of care including biopsies, final specimen pathology and patient outcomes. CLASSICA will validate the use of AI in the analysis of ICG fluorescence for the purposes of classifying significant rectal polyps and tumours endoscopically. Follow-on studies will compare AI-guided targeted biopsy or, indeed, AI characterization alone with traditional biopsy and AI-guided local excision versus traditional excision with regard to marginal clearance and recurrence.

Pitfalls of single-site tattooing of suspicious or significant polyps at colonoscopy in patients undergoing colectomy

This is a case report of a single-site tattooing opposite the index lesion at colonoscopy. At laparoscopic surgery, the tattoo was not visible intraabdominally and on-table flexible sigmoidoscopy revealed that the tattoo was proximal to the scar tissue. Had tattoo been visible, this could have led to adverse effects with the resection point being proximal to or through the lesion. As endoscopic mucosal resection is done in patients lying flat, while surgical procedures are performed in a 30° Trendelenberg, this could have led to relative differences in the position of the tattoo and index lesion. It should become standard practice that all lesions that need tattooing should be done circumferentially distal to the index lesion. When only single-site tattooing is done, if the patient needs surgery, then a preoperative distal tattooing should be done.

Pembrolizumab-Induced Nasal Polyposis: The First Reported Case

The last decade has seen the emergence of immune checkpoint inhibitors for the treatment of a wide variety of cancer types. While these medications are generally speaking well tolerated, the full long-term side effect profiles of these medications have not been fully elucidated. We describe a case of chronic rhinosinusitis with nasal polyposis induced treatment with pembrolizumab, the first reported case. We present the case of a 48-year-old man with a background history of stage IV non-small cell lung cancer with bone metastases. He was commenced on pembrolizumab and over the course of the subsequent 5 years he developed significant nasal polyps bilaterally, and was commenced on medical therapy. Sinus CT scan demonstrated bilateral total opacification of all his sinuses and nasal cavity. He subsequently underwent bilateral functional endoscopic sinus surgery. He remains symptom-free and at his last clinical follow-up visit 1 year later. There are limited case reports of nasal polyposis occurring in patients receiving immune checkpoint inhibitors, with only one case requiring surgery. We describe the first case of severe nasal polyps due to pembrolizumab and successfully treated with polypectomy. From our review, there were no cases that required a cessation of therapy.

PREVALENCE OF SERRATED POLYPS AND THEIR ASSOCIATION WITH SYNCHRONOUS COLORECTAL ADVANCED ADENOMAS.

•This study revealed a similar prevalence of clinically significant serrated polyps and advanced adenomas among patients who underwent colonoscopy. •Multivariate analysis demonstrated an association between clinically significant serrated polyps and synchronous advanced adenomas, though the strength of this association was stronger for proximal advanced adenomas. •Large serrated polyps and sessile serrated adenomas were associated with proximal advanced adenomas. Background - Serrated lesions are the precursors of up to one-third of colorectal cancer (CRC) cases and share molecular and epidemiological features with interval CRC. Previous studies have reported wide variation in serrated polyp prevalence and diverse magnitude of its relationship with synchronous advanced adenomas.Objective - Describe the prevalence of serrated polyps and evaluate their association with synchronous advanced adenomas. Methods - The study is a retrospective analysis of 1208 colonoscopies performed in patients aged 45 to 75, predominantly for CRC screening. Data on the prevalence of serrated polyps subsets and advanced adenomas were collected, and multivariate analysis were performed to identify the association between serrated polyps and synchronous advanced adenomas. Results - The prevalence of clinically significant serrated polyps (CSSP), large serrated polyps (LSP), and sessile serrated adenomas (SSA) were 11.3%, 6%, and 3.7%. CSSP were associated with synchronous advanced adenomas (OR 2.121, 95%CI 1.321-3.406), regardless of proximal (OR 2.966, 95%CI 1.701-5.170) or distal (OR 1.945, 95%CI 1.081-3.499) location, while LSP (OR 2.872, 95%CI 1.425-5.787) and SSA (OR 5.032, 95%CI 2.395-10.576) were associated with proximal advanced adenomas. Conclusion - The prevalence of CSSP and advanced adenomas were alike. CSSP is a risk factor for advanced adenomas, and the strength of this association is stronger for proximal advanced adenomas. LSP and SSA are associated with proximal advanced adenomas.

Quadruple Assessment using Transrectal Ultrasound Scan is Effective at Accurately Facilitating Choice of Excision Plane by Tems in the Complex Specc Lesion

Background: There is currently no consensus as to the optimal imaging modality for Significant Polyps and Early Colorectal Cancer (SPECC). This study describes the use of transrectal ultrasound (TRUSS) as part of a quadruple assessment process to evaluate the depth of invasion of SPECC lesions and guide local excision. Method: Pre-operative imaging and histology were reviewed for all patients undergoing transanal endoscopy microsurgery (TEMS) at Cheltenham General Hospital between 2013 and 2019. Treatment options included mucosectomy, partial thickness excision and full thickness excision. The dataset was studied specifically to evaluate the risk that malignancy will be present at the deep margin. ‘Failure’ of assessment was thus defined as the failure to detect and achieve complete local excision of malignancy. Results: 400 patients were included: 319 primary lesions and 81 secondary lesions. Amongst the primary lesions 93.7% (n=299) had successful R0 excisions. Of the primary lesions with incomplete excisions 50% (N=10) had undergone mucosectomy, 40% (n=8) full thickness excision and 10% (n=2) partial thickness excision

Impact of looping on premalignant polyp detection during colonoscopy

The presence of premalignant polyps on colonoscopy is an indicator of metachronous colorectal cancer. Looping during colonoscopy is associated with old age, female sex, and colonoscopy insertion time. However, the clinical significance of looping is not fully understood. We aimed to clarify the effect of looping on colorectal premalignant polyp detection. To assess the effects of looping on premalignant polyp detection using logistic regression analyses. We retrospectively investigated patients who underwent colonoscopy at Toyoshima Endoscopy Clinic between May, 2017 and October, 2020. From the clinic's endoscopy database, we extracted data on patient age, sex, endoscopist-assessed looping, colonoscopy duration, endoscopist experience, detection rate, and number of premalignant polyps. We assessed 12259 patients (mean age, 53.6 years; men, 50.7%). Looping occurred in 54.3% of the patients. Mild and severe looping were noted in 4399 and 2253 patients, respectively. The detection rates of adenomas, advanced adenomas, high-risk adenomas, clinically significant serrated polyps (CSSPs), and sessile serrated lesions (SSLs) were 44.7%, 2.0%, 9.9%, 8.9% and 3.5%, respectively. The mean numbers of adenomas and SSLs were 0.82 and 0.04, respectively. The detection rates of adenomas, high-risk adenomas, and CSSPs increased with looping severity (all P < 0.001). The number of adenomas increased with looping severity (P < 0.001). Multivariate analyses found that detection of adenomas, high-risk adenomas, and CSSPs was associated with severe looping (P < 0.001, P < 0.001, and P = 0.007, respectively) regardless of age, sex, time required for colonoscope insertion and withdrawal, and endoscopist experience. Looping severity was independently associated with high detection rates of premalignant polyps. Therefore, looping may predict the risk of metachronous colorectal cancer. Endoscopists should carefully examine the colorectum of patients with looping.

S212 Incidence Rates of Adenoamtous Polyps, Clinically Significant Serrated Polyps and Advanced Neoplasia in Adults Age 18-45 in a Community Hospital in the Upper Midwest Over a 15-Year Period: A Retrospective Review

Introduction: Increasing incidence of early onset colorectal cancer over time has been well described. Temporal trends regarding precursor lesions in young adults are less clearly defined. The aim of this study was to investigate trends in the rates of adenomatous colon polyps, clinically significant serrated polyps and advanced neoplasia in young adults over a 15 year period. Methods: We performed a retrospective review of all colonoscopy examinations performed in two community hospitals and an ambulatory surgery center in northern Minnesota between January 1, 2006 and December 31, 2020 in adults age 18-45. Exclusion criteria were incomplete colonoscopy exams or exams with inadequate bowel preparation. A total of 2655 colonoscopy exams were included in our review. We measured the incidence rates of adenomas, clinically significant serrated polyps (sessile serrated polyps, traditional serrated adenomas, proximal hyperplastic polyps > 4 mm and hyperplastic polyps > 9 mm) and rates of advanced neoplasia (adenoma > 9 mm, villous histology, high grade dysplasia, colon cancer) for each year in the study period. The relationship between time (as measured by year) and incidence of adenomatous polyps, clinically significant serrated polyps, advanced neoplasia and non-malignant advanced neoplasia was investigated using Spearman Rank Order Correlation (rho). Preliminary analyses were performed to ensure no violation of the assumptions. Results: There were a total of 291 cases with at least one adenoma detected (11.0% incidence rate), 63 cases with at least one clinically significant serrated polyp (2.4% incidence rate), 60 cases with advanced neoplasia (2.3% incidence) and 8 cases of colorectal cancer (0.3% incidence rate). The incidence rate of adenomatous polyps increased over the course of the study period (rho = .88, n = 15, = p < .001). The incidence of clinically significant serrated polyps increased over the study period, however this finding was not statistically significant. The incidence of advanced neoplasia increased over the course of the study period and trended towards significance (rho = .50, n = 15, p = .056). (Figure) Conclusion: Incidence rates of adenomatous colon polyps in young adults increased over the study period while rates of advanced neoplasia appeared to increase over the study period. More complete understanding of temporal trends in different precursor colon lesions in young adults may help guide endoscopists caring for young adults with lower GI symptoms.Figure 1.: Incidence of adenomatous colon polyps in young adults over time

Brown slits for colorectal adenoma crypts on conventional magnifying endoscopy with narrow band imaging using the X1 system.

BACKGROUNDAccurate diagnosis of colorectal premalignant polyps, including adenomas, is vital in clinical practice. AIMTo investigate the diagnostic yields of novel findings of brown slits for adenomas. METHODSPatients who underwent colonoscopy at the Toyoshima Endoscopy Clinic were enrolled. Polyps sized ≥ 5 mm suspected of adenomas or clinically significant serrated polyps were included in the study. We defined the surface structures of colorectal polyps, which were brown curves inside and along the tubular glands identified using a combination of a new X1 system (Olympus Corporation) and a conventional magnifying colonoscope with non-staining narrow band imaging (NBI), as brown slits. The brown slits corresponded to slit-like lumens on endocytoscopy and histological crypt openings of an adenoma. We evaluated the diagnostic performance of brown slits for adenoma. RESULTSA total of 108 Lesions from 62 patients were eligible. The average age was 60.4 years and 41.9% were male. The mean polyp size was 7.45 ± 2.83 mm. Fifty-seven lesions were positive for brown slits. Histopathological diagnosis comprised 59 low-grade tubular adenomas, 16 sessile serrated lesions, and 33 hyperplastic polyps. Among 59 adenomas, 56 (94.9%) were positive for brown slits. Among 16 sessile serrated lesions, 0 (0%) was positive for brown slits. Among 33 hyperplastic polyps, 1 (3.0%) was positive for brown slits. The sensitivity, specificity, and accuracy of brown slits for adenoma were 94.9%, 98.0%, and 96.3%, respectively. The positive predictive value and negative predictive value of brown slits for adenoma were also excellent for 98.2%, and 94.1%, respectively.CONCLUSIONBrown slits on conventional magnifying endoscopy with non-staining NBI using the X1 system were useful for diagnosing colorectal adenoma. The new endoscopy system could be examined using new standards.

MDT stage migration in MRI of significant rectal polyps and early rectal cancers.

To audit the diagnostic accuracy of MRI for staging early and polyp rectal cancers with the purpose of identifying scope for service improvement. This is an IRB approved retrospective study of patients who underwent staging MRI for rectal growths followed by upfront TME type surgery or local excision without neoadjuvant therapy between 2018 and 2021. MR-T-stage was compared with surgical histopathology. The degree of stage migration in the multidisciplinary team meetings (MDT) was assessed and training needs were identified. 53 patients (32 males) with a mean (SD) age of 56.7 (13.6) years with 54 rectal lesions and underwent trans-anal excision (n = 18) or upfront surgery (n = 35) were included. Pathology showed < / = pT1 stage in n = 18 and > / = pT2 stage in n = 36. Radio-pathological concordance rate was 38.9% and 74.1%, respectively, for primary reports and MDT reads, respectively, and during MDT, the rates improved by 44.5% and 30.5% for < / = pT1 and > / = pT2 stages ,respectively. The overall T-stage migration rate at MDT was 44.6% (25/54) and the migration rate was higher (61.1%) for < / = pT1 stage lesions. The best sensitivity, specificity, PPV, NPV and accuracy of MRI for T-staging was 83.3%, 91.6%, 83.3%, 91.6% and 88.8%, respectively. Radio-pathological correlation for MRI T-stage is excellent for MDT reads by experienced radiologists. MDT reads lead to significant down-staging of T-stage in polyp and early rectal cancer thereby improving radio-path correlation.

Clinically significant serrated polyp detection rates and risk for postcolonoscopy colorectal cancer: data from the New Hampshire Colonoscopy Registry

Higher adenoma detection rates reduce the risk of postcolonoscopy colorectal cancer (PCCRC). Clinically significant serrated polyps (CSSPs; defined as any sessile serrated polyp, traditional serrated adenoma, large [≥1 cm] or proximal hyperplastic polyp >5mm) also lead to PCCRC, but there are no data on associated CSSP detection rates (CSSDRs). We used data from the New Hampshire Colonoscopy Registry (NHCR) to investigate the association between PCCRC risk and endoscopist CSSDR. We included NHCR patients with 1 or more follow-up events: either a colonoscopy or a colorectal cancer (CRC) diagnosis identified through linkage with the New Hampshire State Cancer Registry. We defined our outcome, PCCRC, in 3 time periods: CRC diagnosed 6 to 36 months, 6 to 60 months, or all examinations (6 months or longer) after an index examination. We excluded patients with CRC diagnosed at or within 6 months of the index examination, with incomplete examinations, or with inflammatory bowel disease. The exposure variable was endoscopist CSSDR at the index colonoscopy. Cox regression was used to model the hazard of PCCRC on CSSDR controlling for age, sex, index findings, year of examination, personal history of colorectal neoplasia, and having more than 1 surveillance examination. One hundred twenty-eight patients with CRC diagnosed at least 6 months after their index examination were included. Our cohort included 142 endoscopists (92 gastroenterologists). We observed that the risk for PCCRC 6 months or longer after the index examination was significantly lower for examinations performed by endoscopists with CSSDRsof 3% to<9% (hazard ratio [HR], .57; 95% confidence interval [CI], .39-.83) or 9% or higher (HR, .39; 95% CI, .20-.78) relative to those with CSSDRs under 3%. Our study is the first to demonstrate a lower PCCRC risk after examinations performed by endoscopists with higher CSSDRs. Both CSSDRs of 9% and 3% to<9% had statistically lower risk of PCCRC than CSSDRs of<3%. These data validate CSSDR as a clinically relevant quality measure for endoscopists.

The management of significant polyps and early colorectal cancers over the last 10 years: A single centre retrospective study

Background: In 2015, the significant polyps and early colorectal cancers (SPECC) national development programme was introduced to standardise the assessment and management of these lesions. Our aim was to investigate the variations in the management at our institution.

Colon capsule endoscopy in clinical practice: lessons from a national 5-year observational prospective cohort.

Background and study aims Colon capsule endoscopy (CCE) has been proposed as an alternative to colonoscopy for screening patients at average risk of colorectal cancer (CRC). A prospective national cohort was developed to assess relevance of CCE in real-life practice and its short- and long-term impacts on clinical management. Patients and methods All patients who underwent a CCE in France were prospectively enrolled from January 2011 to May 2016 and reached annually by phone until May 2017. All CCE and colonoscopy reports were systematically collected. Results During the study period, 689 CCEs were analyzed from 14 medical centers. Median follow-up time was 35 months [IQR: 12–50]. Indication for CCE was mainly for elderly patients (median age: 70 years, IQR: [61–79]) due to anesthetic or colonoscopy contraindication (n = 307; 44.6 %). Only 337 CCEs (48.9 %) were both complete and with adequate bowel preparation. Advanced neoplasia (adenoma with high-grade dysplasia or CRC) was diagnosed following 32 CCEs (4.6 %). Among patients who underwent colonoscopy or therapeutic surgery following CCE, 18.8 % of all advanced neoplasias (6/32) had not been diagnosed by CCE mainly due to technical issues. Performing a colonoscopy in the case of significant polyps or insufficient bowel cleansing or after an incomplete CCE allowed the diagnosis of 96.9 % of all identified advanced neoplasias (31/32). Conclusions Outside the scope of academic trials, improvement is needed to increase the reliability of CCE as less than half were considered optimal i. e. complete with adequate bowel cleansing. Most of missed colonic advanced neoplasia were due to incomplete CCE with distal neoplasia location.

A Polyp Worth Removing: A Paradigm for Measuring Colonoscopy Quality and Performance of Novel Technologies for Polyp Detection.

Leaving no significant polyp behind while avoiding risks due to unnecessary resections is a commonsense strategy to safely and effectively prevent colorectal cancer (CRC) with colonoscopy. It also alludes to polyps worth removing and, therefore, worth finding. The majority of "worthy" precancerous polyps are adenomas, which for over 2 decades, have received the most attention in performance research and metrics. Consequently, the detection rate of adenomas is currently the only validated, outcome-based measure of colonoscopy demonstrated to correlate with reduced risk of postcolonoscopy CRC. However, a third or more of postcolonoscopy CRCs originate from sessile serrated polyps (SSPs), which are notoriously difficult to find, diagnose and completely resect. Among serrated polyps, the agreement among pathologists differentiating SSPs from non-neoplastic hyperplastic polyps is moderate at best. This lack of ground truth precludes SSPs from consideration in primary metrics of colonoscopy quality or performance of novel polyp detection technologies. By instead leveraging the distinct endoscopic and clinical features of serrated polyps, including those considered important due to proximal location and larger size, clinically significant serrated polyps represent serrated polyps worth removing, enriched with subtle precancerous SSPs. With the explosion of technologies to assist polyp detection, now is the time to broaden benchmarks to include clinically significant serrated polypss alongside adenomas, a measure that is relevant both for assessing the performance of endoscopists, and for assessing new polyp detection technologies.

Correlation between proximal serrated polyp detection and clinically significant serrated polyps: inter-endoscopist variability

Introduction and aimsThe adenoma detection rate (ADR) is the most important quality indicator for the prevention of colorectal cancer but serrated polyps are also precursor lesions of the disease. The aim of our study was to compare the detection rate of proximal serrated polyps (PSPs) and that of clinically significant serrated polyps (CSSPs) between endoscopists and analyze the relation of those parameters to the ADR. MethodsAn observational, prospective, cross-sectional study was conducted on all patients that underwent colonoscopy at the Policlínico Peruano Japonés within the time frame of July 2015 and August 2016. The ADR and PSP and CSSP detection rates between endoscopists were compared through multivariate logistic regression and the association between those parameters was calculated through the Pearson correlation coefficient. ResultsThe study included 15 endoscopists and 1,378 colonoscopies. The PSP detection rate ranged from 1.8-17% between endoscopists and had an almost perfect correlation with the CSSP detection rate (p = 0.922), as well as strongly correlating with the ADR (p = 0.769). ConclusionsThere was great variability in the PSP detection rate between endoscopists. It also had an almost perfect correlation with the CSSP detection rate and strongly correlated with the ADR. Those results suggest a high CSSP miss rate at endoscopy and a low PSP detection rate.

The American Society of Colon and Rectal Surgeons 2021 Annual Scientific Meeting Abstracts

Purpose/Background: Faecal immunochemical test (FIT) is widely adopted for the screening of colorectal cancer in the United Kingdom. At the start of the coronavirus pandemic we incorporated FIT testing into our department's urgent referral pathway for patients with suspected colorectal cancer. This aimed to triage those symptomatic patients who required urgent investigation and those who were unlikely to have significant colorectal pathology and therefore could have investigations delayed until it was safer and endoscopy services had recovered capacity. This study aimed to identify the diagnostic accuracy of FIT in this setting. Methods/Interventions: Patients referred to our institution under our urgent cancer referral pathway between 28th April and 19th June 2020 were identified from a prospectively kept database. FIT results were accessed from electronic laboratory records. Results were analysed using a threshold of 10ug/ml and the current screening threshold in England of 120ug/ml. Patient outcomes were determined by electronic patient records. Significant polyps included polyps greater than 10mm or meeting British Society of Gastroenterology high risk criteria. Results/Outcome(s): 373 patients were referred to the colorectal department during the study period. 24 referrals did not meet urgent referral criteria. 202 (54%) patients had FIT performed by their general practitioner and 47 (13%) patients had FIT undertaken in the colorectal clinic. In patients who had FIT, 97 (41%) patients had a FIT result less than 10ug/ml and 193 (81%) patients had FIT less than 120ug/ml. 25 (10%) patients were not investigated further based on FIT result and 16 (6%) patients declined further investigation. 13 (3%) patients in the cohort were subsequently investigated and diagnosed with a colorectal cancer (FIT range 24-8438ug/ml). One patient was diagnosed with a gastric cancer (FIT 259ug/ml) and two other patients had incidental findings of other nongastrointestinal cancers. 9 (4%) and 19 (8%) patients had significant colonic polyps and colitis respectively. Other diagnoses included bleeding gastric ulcer (2), angiodysplasia (1) and solitary rectal ulcer syndrome (1). In this symptomatic cohort, with a threshold of 10ug/ml the sensitivity of FIT was 100% and specificity of 36% for the diagnosis of colorectal cancer. At the 120ug/ml threshold the sensitivity was 77% and the specificity 81% for the diagnosis of colorectal cancer. Conclusions/Discussion: Incorporating FIT to triage symptomatic patients with symptoms suggestive of colorectal cancer is feasible with acceptable levels of diagnostic accuracy when utilizing a threshold of 10ug/ml. FIT testing will continue to be incorporated into our urgent cancer referral pathway, although general practitioners may still refer patients with a negative FIT but high clinical suspicion. Further work will continue to audit the use of FIT in this symptomatic setting.