Artificial intelligence in colorectal surgery: an AI-powered systematic review

Artificial intelligence (AI) has the potential to revolutionize surgery in the coming years. Still, it is essential to clarify what the meaningful current applications are and what can be reasonably expected. This AI-powered review assessed the role of AI in colorectal surgery. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-compliant systematic search of PubMed, Embase, Scopus, Cochrane Library databases, and gray literature was conducted on all available articles on AI in colorectal surgery (from January 1 1997 to March 1 2021), aiming to define the perioperative applications of AI. Potentially eligible studies were identified using novel software powered by natural language processing (NLP) and machine learning (ML) technologies dedicated to systematic reviews. Out of 1238 articles identified, 115 were included in the final analysis. Available articles addressed the role of AI in several areas of interest. In the preoperative phase, AI can be used to define tailored treatment algorithms, support clinical decision-making, assess the risk of complications, and predict surgical outcomes and survival. Intraoperatively, AI-enhanced surgery and integration of AI in robotic platforms have been suggested. After surgery, AI can be implemented in the Enhanced Recovery after Surgery (ERAS) pathway. Additional areas of applications included the assessment of patient-reported outcomes, automated pathology assessment, and research. Available data on these aspects are limited, and AI in colorectal surgery is still in its infancy. However, the rapid evolution of technologies makes it likely that it will increasingly be incorporated into everyday practice.

A63 REFINING THE CANADIAN ASSOCIATION OF GASTROENTEROLOGY GUIDELINE ON SCREENING IN PERSONS WITH A FAMILY HISTORY OF NONHEREDITARY COLORECTAL CANCER OR ADENOMA: A MODIFIED DELPHI PROCESS

Background

In 2018, the Canadian Association of Gastroenterology (CAG) published an extensive systematic review and guideline on screening in persons with a family history (FHx) of nonhereditary colorectal cancer (CRC) and adenoma. While CAG’s recommendations were evidence-based, some recommendations lacked precision (e.g. ranges for some start ages & intervals) and screening cessation age was not addressed, leading to implementation challenges for practitioners and CRC screening programs.

Aims

To review and update the evidence since the 2018 guideline and to formulate implementable recommendations in the Ontario context that are aligned with the CAG guideline.

Methods

ColonCancerCheck (Ontario’s organized CRC screening program) conducted a modified version of the literature search used by CAG (Jan 2017 - Sept 2019). A 19-member expert panel with Canadian and international representatives from endoscopy, primary care, epidemiology, organized CRC screening programs, Ontario’s cancer system and the general public refined the recommendations of the CAG guideline for the purposes of implementation in an organized CRC screening program using a modified Delphi process. This iterative process involved a series of webinars and anonymous survey rounds where the panel reviewed evidence materials and provided online feedback to develop, refine & achieve consensus on screening recommendations in persons with a FHx of CRC/adenoma. Consensus was achieved if ≥75% of members agreed or strongly agreed with the statement.

Results

Six new systematic reviews and 2 new guidelines were identified. New evidence included data on the absolute risk (10 year & lifetime risk) of CRC by type of FHx, as well as the performance of fecal immunochemical testing (FIT) and barriers to CRC screening in persons with a FHx of CRC. The expert panel participated in 3 webinars and 4 online surveys to arrive at consensus. Panel recommendations and level of consensus will be reported for the 6 statements (Table).

Conclusions

Building from the CAG guideline, we derived evidence-based and implementable recommendations for screening persons with a FHx of CRC or adenoma.

Funding Agencies

Ontario Health (Cancer Care Ontario)

Colonoscopy quality assessment and accuracy: analysis of the influencing factors and surgical sequelae on 216 colonoscopies

OBJECTIVE

Colonoscopy is recognized as the primary screening test for colorectal cancer. However, its inaccuracy in identifying the exact tumor localization is still high. As a consequence, repeated colonoscopies and changes in the surgical management have been reported. This study aims to evaluate the quality of 216 colonoscopies, to define colonoscopy accuracy and to investigate the surgical sequelae of an incorrect localization.

PATIENTS AND METHODS

A retrospective analysis of 216 colonoscopies has been conducted. Colonoscopy quality was assessed on: quality of bowel preparation, completeness of the examination, video and/or photographic documentation, and reported the distance of the lesion from the anal verge. Colonoscopy accuracy was evaluated in terms of correspondence between the endoscopic and intra-operative tumor localization.

RESULTS

Bowel preparation adequateness was reported in 121 out of 216 (56%) colonoscopies, with an adequate grade in 68.6% of cases. A complete colonoscopy was accomplished in 86.9% of cases with photo documentation in only 59 colonoscopies (27.3%). The lesion distance from the anal verge was documented only in 93 out of 216 colonoscopies. Of the 157 lesions described at the colonoscopy, 117 matched with the intra-operative localization (accuracy 74.5%). Fifteen of the 40 incorrectly localized lesions (37.5%) required changes in the surgical management. At multivariate analysis, the colonoscopy completeness was the only influencing factor on the concordance between endoscopic and intra-operative localization.

CONCLUSIONS

Colonoscopy demonstrated adequate accuracy in localizing lesions. However, the incorrect tumor localization leads to a high rate of changes in surgical management. Increase in.

Barriers against split-dose bowel preparation for colonoscopy

OBJECTIVE

Although split regimen is associated with higher adenoma detection and is recommended for elective colonoscopy, its adoption remains suboptimal. The identification of patient-related barriers may improve its implementation. Our aim was to assess patients' attitude towards split regimen and patient-related factors associated with its uptake.

DESIGN

In a multicentre, prospective study, outpatients undergoing colonoscopy from 8:00 to 14:00 were given written instructions for 4 L polyethylene glycol bowel preparation, offering the choice between split-dose and day-before regimens and emphasising the superiority of split regimen on colonoscopy outcomes. Uptake of split regimen and association with patient-related factors were explored by a 20-item questionnaire.

RESULTS

Of the 1447 patients (mean age 59.2±13.5 years, men 54.3%), 61.7% and 38.3% chose a split-dose and day-before regimens, respectively. A linear correlation was observed between time of colonoscopy appointments and split-dose uptake, from 27.3% in 8:00 patients to 96% in 14:00 patients (p<0.001, χ² for linear trend). At multivariate analysis, colonoscopy appointment before 10:00 (OR 0.14, 95% CI 0.11 to 0.18), travel time to endoscopy service >1 h (OR 0.55, 95% CI 0.38 to 0.79), low education level (OR 0.72, 95% CI 0.54 to 0.96) and female gender (OR 0.74, 95% CI 0.58 to 0.95) were inversely correlated with the uptake of split-dose. Overall, the risk of travel interruption and faecal incontinence was slightly increased in split regimen patients (3.0% vs 1.4% and 1.5% vs 0.9%, respectively; p=NS). Split regimen was an independent predictor of adequate colon cleansing (OR 3.34, 95% CI 2.40 to 4.63) and polyp detection (OR 1.46, 95% CI 1.11 to 1.92).

CONCLUSION

Patient attitude towards split regimen is suboptimal, especially for early morning examinations. Interventions to improve patient compliance (ie, policies to reorganise colonoscopy timetable, educational initiatives for patient and healthcare providers) should be considered.

TRIAL REGISTRATION NUMBER

NCT02287051; pre-result.

Detection rate of serrated polyps and serrated polyposis syndrome in colorectal cancer screening cohorts: a European overview

OBJECTIVE

The role of serrated polyps (SPs) as colorectal cancer precursor is increasingly recognised. However, the true prevalence SPs is largely unknown. We aimed to evaluate the detection rate of SPs subtypes as well as serrated polyposis syndrome (SPS) among European screening cohorts.

METHODS

Prospectively collected screening cohorts of ≥1000 individuals were eligible for inclusion. Colonoscopies performed before 2009 and/or in individuals aged below 50 were excluded. Rate of SPs was assessed, categorised for histology, location and size. Age-sex-standardised number needed to screen (NNS) to detect SPs were calculated. Rate of SPS was assessed in cohorts with known colonoscopy follow-up data. Clinically relevant SPs (regarded as a separate entity) were defined as SPs ≥10 mm and/or SPs >5 mm in the proximal colon.

RESULTS

Three faecal occult blood test (FOBT) screening cohorts and two primary colonoscopy screening cohorts (range 1.426-205.949 individuals) were included. Rate of SPs ranged between 15.1% and 27.2% (median 19.5%), of sessile serrated polyps between 2.2% and 4.8% (median 3.3%) and of clinically relevant SPs between 2.1% and 7.8% (median 4.6%). Rate of SPs was similar in FOBT-based cohorts as in colonoscopy screening cohorts. No apparent association between the rate of SP and gender or age was shown. Rate of SPS ranged from 0% to 0.5%, which increased to 0.4% to 0.8% after follow-up colonoscopy.

CONCLUSIONS

The detection rate of SPs is variable among screening cohorts, and standards for reporting, detection and histopathological assessment should be established. The median rate, as found in this study, may contribute to define uniform minimum standards for males and females between 50 and 75 years of age.

Split-dose preparation for colonoscopy increases adenoma detection rate: a randomised controlled trial in an organised screening programme

OBJECTIVE

Although a split regimen of bowel preparation has been associated with higher levels of bowel cleansing, it is still uncertain whether it has a favourable effect on the adenoma detection rate (ADR). The present study was aimed at evaluating whether a split regimen was superior to the traditional 'full-dose, day-before' regimen in terms of ADR.

DESIGN

In a multicentre, randomised, endoscopist-blinded study, 50-69-year-old subjects undergoing first colonoscopy after positive-faecal immunochemical test within an organised colorectal cancer organised screening programmes were 1:1 randomised to receive low-volume 2-L polyethylene glycol (PEG)-ascorbate solution in a 'split-dose' (Split-Dose Group, SDG) or 'day-before' regimen (Day-Before Group, DBG). The primary endpoint was the proportion of subjects with at least one adenoma. Secondary endpoints were the detection rates of advanced adenomas and serrated lesions at per-patient analysis and the total number of lesions.

RESULTS

690 subjects were included in the study. At per-patient analysis, the proportion of subjects with at least one adenoma was significantly higher in the SDG than in the DBG (183/345, 53.0% vs 141/345, 40.9%, relative risk (RR) 1.22, 95% CI 1.03 to 1.46); corresponding figures for advanced adenomas were 26.4% (91/345) versus 20.0% (69/345, RR 1.35, 95% CI 1.06 to 1.73). At per-polyp analysis, the total numbers of both adenomas and advanced adenomas per subject were significantly higher in the SDG (1.15 vs 0.8, p <0.001; 0.36 vs 0.22, p<0.001).

CONCLUSIONS

In an organised screening setting, the adoption of a split regimen resulted into a higher detection rate of clinically relevant neoplastic lesions, thus improving the effectiveness of colonoscopy. Based on such evidence, the adoption of a split regimen for colonoscopy should be strongly recommended.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02178033.

Efficacy and safety of endoscopic resection of large colorectal polyps: a systematic review and meta-analysis

OBJECTIVE

To assess the efficacy and safety of endoscopic resection of large colorectal polyps.

DESIGN

Relevant publications were identified in MEDLINE/EMBASE/Cochrane Central Register for the period 1966-2014. Studies in which ≥20 mm colorectal neoplastic lesions were treated with endoscopic resection were included. Rates of postendoscopic resection surgery due to non-curative resection or adverse events, as well as the rates of complete endoscopic removal, invasive cancer, adverse events, recurrence and mortality, were extracted. Study quality was ascertained according to Newcastle-Ottawa Scale. Forest plot was produced based on random effect models. I2 statistic was used to describe the variation across studies due to heterogeneity. Meta-regression analysis was also performed.

RESULTS

50 studies including 6442 patients and 6779 large polyps were included in the analyses. Overall, 503 out of 6442 patients (pooled rate: 8%, 95% CI 7% to 10%, I2=78.6%) underwent surgery due to non-curative endoscopic resection, and 31/6442 (pooled rate: 1%, 95% CI 0.7% to 1.4%, I2=0%) to adverse events. Invasive cancer at histology, non-curative endoscopic resection, synchronous lesions and recurrence accounted for 58%, 28%, 2.2% and 5.9% of all the surgeries, respectively. Endoscopic perforation occurred in 96/6595 (1.5%, 95% CI 1.2% to 1.7%) polyps, while bleeding in 423/6474 (6.5%, 95% CI 5.9% to 7.1%). Overall, 5334 patients entered in surveillance, 502/5836 (8.6%, 95% CI 7.9% to 9.3%) being lost at follow-up. Endoscopic recurrence was detected in 735/5334 patients (13.8%, 95% CI 12.9% to 14.7%), being an invasive cancer in 14/5334 (0.3%, 95% CI 0.1% to 0.4%). Endoscopic treatment was successful in 664/735 cases (90.3%, 95% CI 88.2% to 92.5%). Mortality related with management of large polyps was reported in 5/6278 cases (0.08%, 95% CI 0.01% to 0.15%).

CONCLUSIONS

Endoscopic resection of large polyps appeared to be an extremely effective and safe intervention. However, an adequate endoscopic surveillance is necessary for its long-term efficacy.

Spondylodiscitis (Andersson lesion) in psoriatic spondyloarthritis: a rare event successfully treated with an anti-TNF therapy

Spondylodiscitis (Andersson lesion) is an infrequent and late complication of advanced ankilosing arthritis. Scanty data on the efficacy of anti-TNF therapy for these lesions are available. To our knowledge, only few cases of spondylodiscitis occurring in patients with psoriatic arthritis were reported in literature. We describe the case of a patient with psoriatic arthritis who early developed Andersson lesions successfully treated with infliximab plus methotrexate therapy.

Systematic review with meta-analysis: the incidence of advanced neoplasia after polypectomy in patients with and without low-risk adenomas

BACKGROUND

Patients with one to two tubular adenomas <1 cm in size without high-grade dysplasia (low-risk group) are considered at low risk for colorectal cancer. However, it is uncertain whether they have the same risk of subsequent advanced neoplasia as those with no neoplasia at baseline colonoscopy.

AIM

To compare incidence of metachronous advanced neoplasia between patients in the low-risk adenoma group and those without neoplasia at index colonoscopy.

METHODS

Relevant publications were identified by MEDLINE/EMBASE and other databases for the period 1992-2013. Studies comparing the incidence of post-polypectomy advanced neoplasia (adenomas ≥10 mm/high-grade dysplasia/villous or cancer) between the low-risk group and patients without colorectal neoplasia at the first colonoscopy were included. Detection rates for advanced neoplasia at endoscopic surveillance were extracted. Study quality was ascertained according to Newcastle-Ottawa Scale. Forest plot was produced based on random-effect models. Inter-study heterogeneity was assessed using the I(2) statistic.

RESULTS

Seven studies provided data on 11 387 patients. Mean surveillance periods ranged between 2 and 5 years. Altogether, 267 patients with post-polypectomy advanced neoplasia were detected in the two groups. The incidence of advanced neoplasia was 1.6% (119/7308) in those without neoplasia and 3.6% (148/4079) in those with low-risk adenoma, respectively, corresponding to a relative risk of 1.8 (95% CI: 1.3-2.6). Inter-study heterogeneity was only moderate (I(2) : 37%). No publication bias was present.

CONCLUSIONS

Patients with low-risk adenomas at baseline had a higher risk of metachronous advanced neoplasia than the group with no adenomas at baseline, though the absolute risk was low in both groups.

Bowel preparation for colonoscopy: European Society of Gastrointestinal Endoscopy (ESGE) guideline

BACKGROUND AND AIM

This Guideline is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). It addresses the choice amongst regimens available for cleansing the colon in preparation for colonoscopy.

METHODS

This Guideline is based on a targeted literature search to evaluate the evidence supporting the use of bowel preparation for colonoscopy. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was adopted to define the strength of recommendation and the quality of evidence.

RESULTS

The main recommendations are as follows. (1) The ESGE recommends a low-fiber diet on the day preceding colonoscopy (weak recommendation, moderate quality evidence). (2) The ESGE recommends a split regimen of 4 L of polyethylene glycol (PEG) solution (or a same-day regimen in the case of afternoon colonoscopy) for routine bowel preparation. A split regimen (or same-day regimen in the case of afternoon colonoscopy) of 2 L PEG plus ascorbate or of sodium picosulphate plus magnesium citrate may be valid alternatives, in particular for elective outpatient colonoscopy (strong recommendation, high quality evidence). In patients with renal failure, PEG is the only recommended bowel preparation. The delay between the last dose of bowel preparation and colonoscopy should be minimized and no longer than 4 hours (strong recommendation, moderate quality evidence). (3) The ESGE advises against the routine use of sodium phosphate for bowel preparation because of safety concerns (strong recommendation, low quality evidence).

A retrospective analysis of early and late outcome of biodegradable stent placement in the management of refractory anastomotic colorectal strictures

BACKGROUND

Benign colorectal strictures are treated conventionally by endoscopic dilation. Experience using SEMS for benign colonic strictures is limited, and outcomes to date have been disappointing. Refractory colorectal strictures remain challenging to be treated with surgery. Polydioxanone-based stent are biodegradable (BD) stent CE approved for esophageal strictures. This study was designed to investigate retrospectively the safety and the efficacy of these stents for the management of strictures refractory to multiple sessions of dilation.

METHODS

Patients with postsurgical benign strictures located within 20 cm from anal verge, refractory to mechanical or pneumatic dilation (at least 3 sessions) were included in this analysis. Clinical success was defined as the absence of occlusive symptoms and the ability to pass through the stricture with a regular size colonoscope. All patients were predilated before stent placement. Stents were released under fluoroscopic control. All patients were under stool softeners for 3 months. Follow-up was scheduled with endoscopic and fluoroscopic controls within 90 days from stent deployment and afterwards by telephone interview and/or ambulatory consultation.

RESULTS

Eleven patients (7 males, mean age 62.3 ± 8.5 years) were included. Technical success was achieved in all the patients. Stent migration was observed in four patients within the first 2 weeks after stent placement. Stent migration was followed by recurrence of stricture and obstructive symptoms in all the cases. Among the seven patients who completed the process of stent biodegradation, five of them had complete resolution of the stricture and relief of symptoms. Two of 11 patients required surgical treatment during the follow-up period (mean 19.8 (range 42-15) months). The overall success rate of the BD stent was 45 %.

CONCLUSIONS

This retrospective analysis of a limited number of patients demonstrated that nondedicated esophageal BD stents are associated with high risk of migration and clinical success in less than 50 % of patients. Dedicated stents with large diameter and antimigration findings could potentially improve the outcome of patients with refractory benign colorectal strictures.

Meta-analysis: adherence to colorectal cancer screening and the detection rate for advanced neoplasia, according to the type of screening test

BACKGROUND

A variety of tests have been proposed for colorectal cancer (CRC), giving rise to uncertainty regarding the optimal approach. The efficacy and effectiveness of different tests are related to both screened participation and the detection rate.

AIM

To perform a meta-analysis on adherence and detection rates of CRC screening tests.

METHODS

Relevant publications were identified by MEDLINE/EMBASE and other databases for the period 1999-2012. A previous systematic review was used for the period before 1966-1999. RCTs and controlled studies including a direct comparison of the uptake rates among different options for CRC screening were included. Adherence and detection rates for advanced neoplasia and cancer were extracted. Risk for bias was ascertained according to CONSORT guidelines. Forrest plots were produced based on random-effect models.

RESULTS

Fourteen studies provided data on 197 910 subjects. Endoscopic strategies were associated with a lower participation (RR: 0.67, 95% CI: 0.56, 0.80) rate, but a higher detection rate of advanced neoplasia (RR: 3.21, 95% CI: 2.38, 4.32) compared with faecal tests. FIT was superior to g-FOBT with regard to both adherence (RR: 1.16, 95% CI 1.03, 1.30) and detection of advanced neoplasia (RR: 2.28, 95% CI 1.68, 3.10) and cancer (RR: 1.96, 95% CI: 1.2, 3.2).

CONCLUSION

The superior accuracy of endoscopy compared with faecal tests minimised any impact of the participation rate in determining the detection rate of advanced neoplasia in a screening setting.

Randomised clinical trial: low-volume bowel preparation for colonoscopy - a comparison between two different PEG-based formulations

BACKGROUND

Low-volume bowel preparations with polyethylene glycol (PEG) have been shown to provide an equivalent cleansing with improved tolerability as compared with standard PEG bowel preparation for colonoscopy. A new iso-osmotic sulphate-free formulation of PEG-Citrate-Simethicone (PEG-CS) in combination with bisacodyl has been recently developed.

AIM

To compare the quality of bowel cleansing with PEG-CS with bisacodyl vs. PEG-Ascorbate (PEG-ASC) in adult out-patients undergoing colonoscopy.

METHODS

Randomised, observer-blind, parallel group study in adult out-patients undergoing colonoscopy in five Italian centres. Both preparations were taken the evening before the procedure. Subjects were instructed to take 2-4 tablets of 5 mg bisacodyl at 16:00 hours and 2 L of PEG-CS at 20:00 hours or 2 L of PEG-ASC plus 1 L of additional water the day before colonoscopy. Bowel cleansing was evaluated according to the Boston Bowel Preparation Scale (≥6 scores were considered as 'clinical success'), and mucosal visibility according to a 3-point scale. Tolerability, acceptability and compliance were also evaluated.

RESULTS

Four hundred and eight patients were randomly allocated to PEG-CS and bisacodyl (n = 204, male patient 48%, mean age 59.1 years) or PEG-ASC (n = 204, male patient 51%, age 59.4 years). In the planned per-protocol analysis, the rate of successful preparation was 79.1% following PEG-CS with bisacodyl, and 70% following PEG-ASC (P < 0.05). Mucosal visibility was evaluated as optimal in 56.1% in the PEG-CS and bisacodyl and 46.3% in the PEG-ASC group (P < 0.05). There were no serious adverse events (AE) in each of the two experimental groups. Two subjects in the PEG-ASC group discontinued the study because of AE.

CONCLUSIONS

Polyethylene glycol-Citrate-Simethicone in combination with bisacodyl was more effective for bowel cleansing than PEG-ASC for out-patient colonoscopy. Tolerability, safety, acceptability and compliance of the two low-volume bowel preparations were similar.

European Society of Gastrointestinal Endoscopy (ESGE) Guideline Development Policy

Numerous scientific publications explore the field of gastrointestinal (GI) endoscopy (a Pubmed search currently yields > 73000 results). Therefore, guidelines have become an indispensable tool for incorporating up-to-date knowledge into daily clinical care. Since the 1990 s, the issuing of guidelines has been a central task of the European Society of Gastrointestinal Endoscopy (ESGE). Here, the ESGE clarifies the types of policy documents that it issues and the methodology used to produce them, taking into account recent methodological developments.

Colon capsule endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

PillCam colon capsule endoscopy (CCE) is an innovative noninvasive, and painless ingestible capsule technique that allows exploration of the colon without the need for sedation and gas insufflation. Although it is already available in European and other countries, the clinical indications for CCE as well as the reporting and work-up of detected findings have not yet been standardized. The aim of this evidence-based and consensus-based guideline, commissioned by the European Society of Gastrointestinal Endoscopy (ESGE) is to furnish healthcare providers with a comprehensive framework for potential implementation of this technique in a clinical setting.

Endoscopist-directed propofol administration versus anesthesiologist assistance for colorectal cancer screening: a cost-effectiveness analysis

BACKGROUND

Propofol for colonoscopy is largely administered by anesthesiologists or anesthesiology nurses in the United States (US) and Europe. Endoscopist-directed administration of propofol (EDP) by nonanesthesiologists has recently been proposed, with potential savings of anesthetist reimbursement costs. We aimed to assess potential EDP-related benefit in a screening setting.

METHODS

In a Markov model the total number of screening and follow-up colonoscopies in a cohort of 100 000 US subjects were estimated. Anesthetist-assisted colonoscopy was compared with an EDP strategy. Model outputs were projected onto the 50 - 80-year-old US population, assuming 27 % as the current uptake for colonoscopy screening. Anesthetist costs were estimated using the mean reimbursement for the corresponding Medicare code (≥ 65-year-olds) and from commercial insurance information (50 - 64-year-olds). The proportion of colonoscopies with anesthesiologist assistance was estimated from the Medicare database. Mean nurse salary was used to estimate the cost of a 2-week EDP training. The absolute number of US endoscopists was estimated by inflating by 33 % the number of board-certified gastroenterologists. No EDP mortality was assumed in the reference scenario, and 0.0008 % mortality in the sensitivity analysis. US census data were adopted. Analogous inputs were used for France to assess EDP-related benefit in a European country.

RESULTS

EDP training for 17 166 nurses (one for each US endoscopist) showed a cost of $ 47 million. Cost estimates for anesthesiologist assistance for colonoscopy were $ 95 (Medicare) and $ 450 (non-Medicare commercial insurance), with 34.8 % of colonoscopies requiring anesthesiologist assistance. US implementation of an EDP policy showed a 10-year saving of $ 3.2 billion (Monte Carlo analysis 5 - 95 % percentiles $ 2.7 - $ 11.9 billion). In the sensitivity analysis, assuming 50 % of colonoscopies were anesthetist-assisted showed an EDP benefit of $ 4.6 billion. Assuming a 0.0008 % mortality rate, the incremental cost - effectiveness of anesthetist-assisted colonoscopy versus an EDP policy was $ 1.5 million per life-year gained, supporting EDP as the optimal choice. A 31-fold increase of EDP-related mortality or a 17-fold cost reduction for anesthetist-assisted colonoscopy was required for EDP to become not cost-effective in this scenario. Implementation of an EDP policy in France, within a guaiac-fecal occult blood test (g-FOBT) screening program, was estimated to save € 0.8 billion in 10 years.

CONCLUSIONS

The absolute economic benefit of EDP implementation in a screening setting is probably substantial with 10-year savings of $3.2 billion in the US and €0.8 billion in France. The impact of an eventual EDP-related mortality on EDP cost - effectiveness seems marginal. The huge economic and medical resources entailed by anesthetist-assisted colonoscopy could be more efficiently invested in other clinical fields.

Rheumatoid arthritis: a complication of aromatase inhibitor therapy?

We report the case of a 56-year-old woman treated with aromatase inhibitors for a breast cancer. Following one year of such therapy, the patient presented with widespread osteoarthrealgia. The clinical picture worsened 3 years later when the pain became more severe with swelling and stiffness involving several joints in a symmetric fashion. Biochemical analysis showed an increase of ESR, CRP and rheumatoid factor, as well as of anti-CCP antibodies. The x-ray was compatible with a diagnosis of rheumatoid arthritis (RA). Therapy with methotrexate, prednisol one, bisphosphonates and vitamin D was started, achieving a quick clinical remission. Aromatase inhibitors have been shown to alter the distribution of Th1/Th2 lymphocytes and increase the level of RANKL. A possible role of aromatase inhibitors in RA development has been further addressed.

Efficacy and safety of endoscopic submucosal dissection for colorectal neoplasia: a systematic review

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) has been proposed for large colorectal lesions, due to the high risk of recurrence following endoscopic mucosal resection. However, data on the efficacy and safety of colorectal ESD are still controversial. The aim of the current systematic review was to assess the efficacy and safety of colorectal ESD.

METHODS

A detailed Medline search of papers published during the period 1999-2010 was performed, using the search terms "Endoscopic submucosal dissection," "Colorectal neoplasia," "Colon," or "Rectum." Published studies that evaluated ESD for colorectal lesions were assessed using well-defined inclusion/exclusion criteria, including histological confirmation and surgery for complications. The process was independently performed by two authors. Forest plots on primary (i.e. histologically verified R0 resection and surgery for ESD complications) and secondary end-points were produced based on random-effect models. Heterogeneity was assessed using the I2 statistic. Risk for within-study bias was also ascertained.

RESULTS

A total of 22 studies (20 Asian, two European) provided data on 2841 ESD-treated lesions. The per-lesion summary estimate of R0 resection rate was 88% (95%CI 82%-92%; I2=91%). At meta-regression, carcinoid vs. non-carcinoid series (R0 93% vs. 87%; P=0.04) and Asian vs. European series (R0 88% vs. 65%; P=0.03) appeared to explain the detected heterogeneity. The per-lesion summary estimate of surgery for ESD complications was 1% (95%CI 0%-1%) with a moderate degree of heterogeneity (I2=49%). However, subgrouping of these results according to histological tumor types was not available in the reviewed studies.

CONCLUSIONS

ESD appeared to be an extremely effective technique to achieve R0 resection of large colorectal lesions. The very low rate of surgery for complications also shows the potential safety of this approach.

Safety of cold polypectomy for <10mm polyps at colonoscopy: a prospective multicenter study

BACKGROUND

Cold polypectomy techniques (without electrocautery) by means of biopsy forceps or snare are widely adopted for the removal of subcentimetric polyps. However, few data are available on the safety of this approach. The aim of this study was to assess the safety of cold polypectomy for subcentimetric polyps, as well as the rate of advanced neoplasia in these lesions.

PATIENTS AND METHODS

In a prospective multicenter trial, consecutive patients with at least one < 10-mm polyp at colonoscopy were prospectively included. All of the < 10-mm polyps detected within the study period were removed by cold polypectomy. The rates of immediate or delayed bleeding and other complications were assessed at 7 and 30 days after cold polypectomy by telephone calls. The rate of advanced histology was also assessed. Predictive variables of postpolypectomy bleeding or advanced neoplasia were identified by multivariate analysis.

RESULTS

A total of 1015 < 10-mm polyps in 823 patients (15.5 % on antiplatelet agents) were removed. Of these, 822 (81 %) were ≤ 5 mm and 193 (19 %) were 6 - 9 mm. Immediate postpolypectomy bleeding occurred in 18 patients, corresponding to a per-patient and per-polyp bleeding rate of 2.2 % (95 % confidence interval [CI] 1.2 % - 3.2 %) and 1.8 % (95 %CI 1 % - 2.6 %), respectively. Therapy with antiplatelet agents (odds ratio [OR] 4; 95 %CI 1.5 - 10.6) and larger polyp size (OR 2; 95 %CI 1.1 - 6.9) were independent predictors of bleeding. Bleeding was successfully treated by endoscopic hemostasis in all cases and required no further medical intervention. Advanced neoplasia prevalence in polyps ≤ 5 mm was as high as 8.7 %.

CONCLUSIONS

The results from this study showed the high safety of a cold polypectomy approach for subcentimetric polyps. This was due to the low rate of postpolypectomy bleeding and to the high efficacy of endoscopic hemostasis in its treatment. The high rate of advanced neoplasia in polyps ≤ 5 mm should prompt some caution on the management of these lesions following detection at computed tomography colonography or colon capsule endoscopy.

Cost effectiveness and projected national impact of colorectal cancer screening in France

BACKGROUND

Colorectal cancer (CRC) is a major cause of morbidity and mortality in France. Only scanty data on cost-effectiveness of CRC screening in Europe are available, generating uncertainty over its efficiency. Although immunochemical fecal tests (FIT) and guaiac-based fecal occult blood tests (g-FOBT) have been shown to be cost-effective in France, cost-effectiveness of endoscopic screening has not yet been addressed.

METHODS

Cost-effectiveness of screening strategies using colonoscopy, flexible sigmoidoscopy, second-generation colon capsule endoscopy (CCE), FIT and g-FOBT were compared using a Markov model. A 40 % adherence rate was assumed for all strategies. Colonoscopy costs included anesthesiologist assistance. Incremental cost-effectiveness ratios (ICERs) were calculated. Probabilistic and value-of-information analyses were used to estimate the expected benefit of future research. A third-payer perspective was adopted.

RESULTS

In the reference case analysis, FIT repeated every year was the most cost-effective strategy, with an ICER of €48165 per life-year gained vs. FIT every 2 years, which was the next most cost-effective strategy. Although CCE every 5 years was as effective as FIT 1-year, it was not a cost-effective alternative. Colonoscopy repeated every 10 years was substantially more costly, and slightly less effective than FIT 1-year. When projecting the model outputs onto the French population, the least (g-FOBT 2-years) and most (FIT 1-year) effective strategies reduced the absolute number of annual CRC deaths from 16037 to 12916 and 11217, respectively, resulting in an annual additional cost of €26 million and €347 million, respectively. Probabilistic sensitivity analysis demonstrated that FIT 1-year was the optimal choice in 20% of the simulated scenarios, whereas sigmoidoscopy 5-years, colonoscopy, and FIT 2-years were the optimal choices in 40%, 26%, and 14%, respectively.

CONCLUSIONS

A screening program based on FIT 1-year appeared to be the most cost-effective approach for CRC screening in France. However, a substantial uncertainty over this choice is still present.

How to predict a high rate of inappropriateness for upper endoscopy in an endoscopic centre?

BACKGROUND

Inappropriateness of upper endoscopy (EGD) indication causes decreased diagnostic yield. Our aim of was to identify predictors of appropriateness rate for EGD among endoscopic centres.

METHODS

A post-hoc analysis of two multicentre cross-sectional studies, including 6270 and 8252 patients consecutively referred to EGD in 44 (group A) and 55 (group B) endoscopic Italian centres in 2003 and 2007, respectively, was performed. A multiple forward stepwise regression was applied to group A, and independently validated in group B. A <70% threshold was adopted to define inadequate appropriateness rate clustered by centre.

RESULTS

discrete variability of clustered appropriateness rates among the 44 group A centres was observed (median: 77%; range: 41-97%), and a <70% appropriateness rate was detected in 11 (25%). Independent predictors of centre appropriateness rate were: percentage of patients referred by general practitioners (GP), rate of urgent examinations, prevalence of relevant diseases, and academic status. For group B, sensitivity, specificity and area under receiver operating characteristic curve of the model in detecting centres with a <70% appropriateness rate were 54%, 93% and 0.72, respectively.

CONCLUSIONS

A simple predictive rule, based on rate of patients referred by GPs, rate of urgent examinations, prevalence of relevant diseases and academic status, identified a small subset of centres characterised by a high rate of inappropriateness. These centres may be presumed to obtain the largest benefit from targeted educational programs.

Systematic review: the role of self-expanding plastic stents for benign oesophageal strictures

BACKGROUND

Treatment of refractory or recurrent benign oesophageal strictures is demanding and surgery may be the only available option. The role of self-expanding plastic stents (SEPS) in the treatment of these strictures is still controversial because of the conflicting results of various studies.

AIM

To analyse with regard to SEPS: technical and clinical success, factors associated with outcome, and safety.

METHODS

Pooled-data analysis of a systematic review of the literature. Clinical success was defined as no need for further endoscopic or surgical treatment after SEPS removal.

RESULTS

Data of 10 studies with 130 treated patients were included. SEPS insertion was technically successful in 128 of 130 patients (98%, 95% CI = 96-100%). Clinical success was achieved in 68 patients (52%, 95% CI = 44-61%) and this was found to be lower in those with a cervical localization of the stricture (33% vs. 54%; P < 0.05). Early (<4 weeks) migration of the stent was reported in 19 (24%, 95% CI = 14-32%) cases, while post-insertion endoscopic re-intervention was required in 25 (21%, 95% CI = 14-28%). Major clinical complications occurred in 12 patients (9%, 95% CI = 4-14%), resulting in death of one (0.8%) patient.

CONCLUSIONS

Our pooled-data analysis showed a favourable risk/benefit ratio when SEPS are applied in patients with recurrent or refractory benign oesophageal strictures. This supports the use of SEPS before referring patients to surgery, and they are a valuable alternative to repeat endoscopic dilation.

Appropriateness of the indication for upper endoscopy: a meta-analysis

BACKGROUND

Application of appropriate indications for upper endoscopy (EGD) should conserve limited endoscopic resources. To perform a systematic review and meta-analysis to assess the efficacy of American Society for Gastrointestinal Endoscopy and European Panel on the Appropriateness of Gastrointestinal Endoscopy guidelines in selecting patients referred for an upper endoscopy relative to the detection of gastro-oesophageal cancer.

METHODS

Studies comparing the appropriateness of EGD indication according to American Society for Gastrointestinal Endoscopy or European Panel on the Appropriateness of Gastrointestinal Endoscopy guidelines and the detection of relevant endoscopic findings and cancer were identified by searching the Medline (1982 to September 2008). Pre-defined outputs of the meta-analysis were sensitivity, specificity, and positive and negative likelihood ratios (LR+, LR-).

RESULTS

We included eight cohort studies comprising 13,856 patients; 10,643 EGD indications were categorized as appropriate, and 3010 (22%) as inappropriate. For relevant findings, the adjusted sensitivity, specificity, LR+, and LR- were 85% (95% CI, 84-86%), 28% (95% CI, 27-29%), 1.18 (95% CI, 1.1-1.3) and 0.6 (95% CI, 0.5-0.7), respectively. For cancer detection, the adjusted sensitivity, specificity, LR+, and LR- were 97% (95% CI, 94-98%), 22% (95% CI, 22-23%), 1.2 (95% CI, 1.1-1.4), and 0.2 (95% CI, 0.05-0.9), respectively.

CONCLUSIONS

For inappropriate EGD, the very low likelihood of cancer argues against endoscopic referral, whereas the low specificity substantially reduces the predictive value of an appropriate indication for both cancer and relevant endoscopic findings.

Systematic review: distribution of advanced neoplasia according to polyp size at screening colonoscopy

BACKGROUND

The impact of not referring sub-centimetre polyps identified at CT colonography upon the efficacy of colorectal cancer screening remains uncertain.

AIM

To determine the distribution of advanced neoplasia according to polyp size in a screening setting.

METHODS

Published studies reporting the distribution of advanced adenomas in asymptomatic screening cohorts according to polyp size were identified by MEDLINE and EMBASE searches. Predefined outputs were the screening rates of advanced adenomas represented by diminutive (< or =5 mm), small (6-9 mm), sub-centimetre (<10 mm) and large (> or =10 mm) polyp sizes.

RESULTS

Data from four studies with 20 562 screening subjects met the primary inclusion criteria. Advanced adenomas were detected in 1155 (5.6%) subjects (95% CI = 5.3-5.9), corresponding to diminutive, small and large polyps in 4.6% (95% CI = 3.4-5.8), 7.9% (95% CI = 6.3-9.4) and 87.5% (95% CI = 86-89.4) of cases respectively. The frequency of advanced lesions among patients whose largest polyp was diminutive, small, sub-centimetre and large in size was 0.9%, 4.9%, 1.7% and 73.5% respectively.

CONCLUSIONS

Based on this systematic review, a 6-mm polyp size threshold for polypectomy referral would identify over 95% of subjects with advanced adenomas, whereas a 10-mm threshold would identify 88% of cases.

Cost-effectiveness of early colonoscopy surveillance after cancer resection

BACKGROUND

Short-interval surveillance colonoscopy at 1 year has been recently recommended following curative-intent surgery for colorectal cancer. However, the efficacy and cost-effectiveness of this endoscopic strategy is largely unknown.

AIM

To assess the clinical and economic impact of early surveillance post-surgical colonoscopy at 1 year in relation to the detection of metachronous colorectal cancer.

METHODS

A decision analysis model was constructed in order to compare a strategy of 1-year endoscopic surveillance versus no early endoscopy following surgical resection for colorectal cancer. A 2-year cancer upstaging was modelled in order to simulate cancer progression in patients with metachronous colorectal cancer who were not referred to early endoscopy. Endoscopic prevalence of metachronous colorectal cancer was estimated from a previous pooled data analysis based on systematic review of the literature. Costs of colonoscopy and cancer care were estimated from Medicare reimbursement data. Outcome measures were the number of early colonoscopies needed to detect one case of cancer or to prevent one cancer-related death and the incremental cost-effectiveness ratio.

RESULTS

The number of early 1-year colonoscopies needed to detect one colorectal cancer and to prevent one colorectal cancer-related death was 143 and 926, respectively. The incremental cost-effectiveness ratio of the early 1-year colonoscopy as compared to a policy of not performing it was $40,313 per life-year gained. The incremental cost-effectiveness ratio of performing early surveillance colonoscopy was sensitive to the changes in cancer prevalence. However, only a reduction from the baseline value of 0.7% to 0.19% was associated with an incremental cost-effectiveness ratio higher than $150,000. Other assumptions about cancer upstaging, initial distribution of cancer, and costs had a lesser influence on incremental cost-effectiveness ratio differences.

CONCLUSIONS

Our study shows that the recently recommended short-interval 1-year surveillance colonoscopy following colorectal cancer resection is a clinically efficient and cost-effective strategy in terms of cancer detection and cancer-specific death prevention.

Systematic review: distribution of advanced neoplasia according to polyp size at screening colonoscopy

BACKGROUND

The impact of not referring sub-centimetre polyps identified at CT colonography upon the efficacy of colorectal cancer screening remains uncertain.

AIM

To determine the distribution of advanced neoplasia according to polyp size in a screening setting.

METHODS

Published studies reporting the distribution of advanced adenomas in asymptomatic screening cohorts according to polyp size were identified by MEDLINE and EMBASE searches. Predefined outputs were the screening rates of advanced adenomas represented by diminutive (< or =5 mm), small (6-9 mm), sub-centimetre (<10 mm) and large (> or =10 mm) polyp sizes.

RESULTS

Data from four studies with 20 562 screening subjects met the primary inclusion criteria. Advanced adenomas were detected in 1155 (5.6%) subjects (95% CI = 5.3-5.9), corresponding to diminutive, small and large polyps in 4.6% (95% CI = 3.4-5.8), 7.9% (95% CI = 6.3-9.4) and 87.5% (95% CI = 86-89.4) of cases respectively. The frequency of advanced lesions among patients whose largest polyp was diminutive, small, sub-centimetre and large in size was 0.9%, 4.9%, 1.7% and 73.5% respectively.

CONCLUSIONS

Based on this systematic review, a 6-mm polyp size threshold for polypectomy referral would identify over 95% of subjects with advanced adenomas, whereas a 10-mm threshold would identify 88% of cases.

Management and long-term follow-up of early stage H. pylori-associated gastric MALT-lymphoma in clinical practice: an Italian, multicentre study

BACKGROUND/AIM

Data on management and long-term follow-up of Helicobacter pylori-associated MALT-lymphoma in clinical practice are scanty. We evaluate the long-term efficacy of H. pylori eradication on low-grade MALT-lymphoma, and the efficacy of further therapies in refractory patients.

METHODS

This study enrolled patients with stages I-II(1) MALT-lymphoma and H. pylori infection. H. pylori eradication was attempted in all patients. Patients with lymphoma persistence or progression following H. pylori treatments received further lymphoma treatments. Both 5-year and disease-free survivals were calculated.

RESULTS

Sixty patients (stage I/II(1): 50/10) were followed up for a median time of 65 months (range 7-156). H. pylori infection was successfully eradicated in 53 (88.3%) patients following three consecutive therapeutic attempts, and lymphoma regressed in 42 (79.2%) of these patients. Sixteen patients received anti-neoplastic treatments due to either lymphoma persistence or progression, and lymphoma was cured in 14 (87.5%) cases. At follow-up, lymphoma relapsed in 13/42 (30.9%) patients within a median time of 19 months (range 3-41), and all but 1 patient were cured with further therapies. Overall, lymphoma regression was achieved in 56 patients (93.3%). The 5-year and disease-free survivals were 94.7% and 74.6%, respectively.

CONCLUSIONS

In clinical practice, a conservative approach with antibiotic eradication seems to be appropriate management for early-stage MALT-lymphoma, with oncologic therapy being reserved for those patients who fail to respond to H. pylori therapy.