Factors associated with reclassification of hyperplastic polyps after pathological reassessment from screening and surveillance colonoscopies

Introduction

A substantial interobserver variation in the differential diagnosis of hyperplastic polyps (HPs) and sessile or traditional serrated adenomas (SSAs/TSAs) has been described.

Methods

The aim of this study is to determine the magnitude of reclassification of HPs and associated factors after pathological reassessment of specimens from screening and surveillance colonoscopies, and to estimate its consequences for follow-up recommendations.

Results

Among 1694 screening and surveillance colonoscopies, a total of 536 polyps were initially diagnosed as HPs and remained unchanged in 88.5 % (n?=?474), whereas 7.6 (n?=?41) and 1.1 % (n?=?6) were reclassified as SSA and TSA, respectively. Compared to definite HPs, SSAs were found more frequently in men than in women (82.9 vs. 61.2 %, p?<?0.05), and in individuals ≥65.0 years (51.2 vs. 31.6 %, p?=?0.05). Also, more SSAs were >5 mm in size (36.6 vs. 6.3 %, p?<?0.05) and were localized in the proximal colon (31.7 vs. 11.8 %, p?<?0.05). In a mixed model analysis, age ≥65.0 years (OR 4.13, 95 % CI 1.22–14.2), snare polypectomy (OR 23.6, 95 % CI 4.86–115), and coincident advanced adenomas (OR 7.56, 95 % CI 1.31–43.5) were significantly (p?<?0.05) associated with reclassification to SSAs. Only 0.53 % of patients had received false recommendations for follow-up visits based on the incorrect HP diagnosis. A c.1799T>A, p.V600E BRAF mutation was detected in 21.9 % (n?=?9) of reclassified SSAs.

Conclusion

Considering these factors may be helpful in serrated lesions that are difficult to allocate. Incorrect recommendations regarding control colonoscopy intervals due to misdiagnosed HPs can explain only a small fraction of interval colorectal cancers.

     

Serrated adenoma prevalence in inflammatory bowel disease surveillance colonoscopy,and characteristics revealed by chromoendoscopy and virtual chromoendoscopy

BACKGROUND:

Sessile or nonpolypoid neoplastic lesions, including sessile serrated adenomas (SSAs), are difficult to detect in patients with inflammatory bowel disease (IBD).

OBJECTIVES:

To assess the prevalence and endoscopic features of SSA in IBD patients undergoing surveillance colonoscopy using novel endoscopic techniques.

METHODS:

Histology results of biopsies from a cohort of 87 patients (47 men; median age 51.4 years; median duration of disease 16.9 years; ulcerative colitis [n=40], Crohn disease [n=43], ischemic colitis [n=4]) with longstanding colonic IBD undergoing surveillance colonoscopy were reviewed. Lesions of dysplasia (adenoma-like mass, or dysplasia-associated lesion or mass), SSAs, adenoma-like polyps, hyperplastic polyps and inflammatory polyps were identified. Surveillance colonoscopy using high-definition alone, or with iScan (Pentax, USA) dye-sprayed or virtual chromoendoscopy was performed. Lesion characteristics were described before histological diagnosis.

RESULTS:

Fourteen SSAs were detected in 87 (11%) IBD patients. The endoscopic characteristics of SSA lesions were: nonpolypoid appearance (86%), predominant localization in the proximal colon (79%), >6 mm in size (79%), cloudy cover (64%), Kudo pit pattern modified type IIO (86%) and irregular spiral vascular pattern (79%). Among the 44 SSAs and hyperplastic polyps found in the present study, the above characteristics of SSA at colonoscopy had a sensitivity of 92.86% (95% CI 66.06% to 98.8%) and specificity of 93.33% (95% CI 77.89% to 98.99%) in predicting a histological diagnosis of SSA (positive predictive value 86.67%, negative predictive value 96.55%).

CONCLUSION:

SSAs are a common finding at surveillance colonoscopy in IBD and have several characteristic features. Further studies are needed to evaluate the natural history of these lesions in IBD patients.     

Serrated Colonic Polyps in a Teaching Hospital in Saudi Arabia: Prevalence and Review of Classification

Background/Aim:

To determine the prevalence of serrated colorectal polyps in the King AbdulAziz University Hospital population and to review the current classification of colorectal serrated polyps with emphasis on morphological features.

Materials and Methods:

This retrospective study used cases diagnosed with serrated colorectal polyps at the histopathology laboratory of King AbdulAziz University Hospital during last five years (2004-2008). The slides were reexamined microscopically and the lesions were renamed according to the terminology discussed in this article.

Results:

Diagnosed hyperplastic polyps represented 12.3% of all colorectal polyps submitted to our laboratory during the study period. However, the false positive rate was found to be 42.5%. Of the truly diagnosed serrated polyps, the most common subtype is the microvesicular serrated polyps. The majority of the serrated colorectal polyps was found in males, with a wide age range.

Conclusion:

The prevalence of serrated colorectal polyps in our geographic area seems to be similar to that in western populations.     

Management of Serrated Polyps of the Colon

Purpose of Review

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

Recent Findings

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

Summary

SPs and SSA/Ps in particular are important colorectal cancer precursors that merit special attention to ensure adequate detection, resection, and surveillance.

     

A Matched Case-Control Study Using the Propensity Score on Differences in the Characteristics of Colorectal Polyps between Younger and Older Koreans: Proximal Shift in the Distribution of Colorectal Polyps among Older Koreans

Background/Aims

Several studies have found that the frequency of colorectal polyps increases significantly from the age of 50 years. The goal of this study was to determine the differences in the clinical characteristics of colorectal polyps between patients aged 50 years and older, and younger patients.

Methods

The colonoscopy database of 3,304 patients at the Yeungnam University Medical Center between January 2009 and December 2009 was reviewed retrospectively. In total, 679 patients were divided into the younger group (n=170) and the older group (aged ≥50 years) (n=509). A matched case-control study was performed using propensity scores and 117 patients selected from each group.

Results

Compared to the younger group, the older group had a significantly higher proportion of female patients, and patients with hypertension, a smoking history, and a history of taking medications. After performing the matched case-control study, 234 patients and 679 colon polyps were included in the analysis. Compared to the younger patients, the older patients had a significantly higher proportion of multiple lesions (57.3% vs 25.6%, p<0.001), left- and right-side distribution (35.9% vs 12.0%, p<0.001), and larger polyps (mean 9.1 mm vs 6.3 mm, p<0.001). A left-sided distribution was less common in the older group than in the younger group (35.0% vs 51.3%, p=0.025).

Conclusions

The methods used to screen for colorectal cancer in older patients should include colonoscopy due to the shift to the right side as a common location for colorectal polyps in that age group.     

A simple method to improve adenoma detection rate during colonoscopy: Altering patient position

BACKGROUND:

Colonoscopy is currently considered to be the gold standard method for detecting and removing adenomatous polyps. However, tandem colonoscopy studies reveal a pooled polyp miss rate of 22%.

OBJECTIVE:

A prospective randomized trial was conducted to assess whether alteration of patient position during colonoscopy withdrawal increases the adenoma detection rate (ADR).

METHOD:

The study group included 120 patients who presented for elective colonoscopic examination. After reaching the cecum, patients were randomly assigned in a 1:1 ratio to examination in either the left lateral position or other positions (left lateral position for the cecum, ascending colon and hepatic flexure; supine for transverse colon; and supine and right lateral position for splenic flexure, descending and sigmoid colon) first. Examination of the colon was performed segment by segment. The size, morphology and location of all polyps were recorded. Polyps were removed immediately after examination of a colon segment when all positions were completed. ADR and polyp detection rates (PDR) were calculated.

RESULTS:

A total of 102 patients completed the study. Examination in the left lateral position revealed 66 polyps in 31 patients (PDR 30.3%) and 42 adenomas in 24 patients (ADR 23.5%). PDR increased to 43.1% (81 polyps in 44 patients) and the ADR to 33.3% (53 adenomas in 34 patients) after the colon was examined in the additional positions (P<0.001 and P=0.002, respectively). The increase in the number of adenomas detected was statistically significant in the transverse and sigmoid colon. The addition of position changes led to a 9.8% increase in the ADR in the transverse colon, splenic flexure, and descending and sigmoid colon. The frequency of surveillance interval was shortened in nine (8.8%) patients after examination of the colon in dynamic positions.

CONCLUSION:

Alteration of patient position during colonoscopy withdrawal is a simple and effective method to improve ADR.     

Treatment and surveillance of polypoid lesions of the gallbladder in the United Kingdom

Objectives

The increase in the routine use of abdominal imaging has led to a parallel surge in the identification of polypoid lesions in the gallbladder. True gallbladder polyps (GBP) have malignant potential and surgery can prevent or treat early gallbladder cancer. In an era of constraint on health care resources, it is important to ensure that surgery is offered only to patients who have appropriate indications. The aim of this study was to assess treatment and surveillance policies for GBP among hepatobiliary and upper gastrointestinal tract surgeons in the UK in the light of published evidence.

Methods

A questionnaire on the management of GBP was devised and sent to consultant surgeon members of the Association of Upper Gastrointestinal Surgeons (AUGIS) of Great Britain and Ireland with the approval of the AUGIS Committee. It included eight questions on indications for laparoscopic cholecystectomy and surveillance based on GBP (size, number, growth rate) and patient (age, comorbidities, ethnicity) characteristics.

Results

A total of 79 completed questionnaires were returned. The vast majority of surgeons (>75%) stated that they would perform surgery when a single GBP reached 10 mm in size. However, there was a lack of uniformity in the management of multiple polyps and polyp growth rate, with different surveillance protocols for patients treated conservatively.

Conclusions

Gallbladder polyps are a relatively common finding on abdominal ultrasound scans. The survey showed considerable heterogeneity among surgeons regarding treatment and surveillance protocols. Although no randomized controlled trials exist, national guidelines would facilitate standardization, the formulation of an appropriate algorithm and appropriate use of resources.     

Sessile serrated adenoma/polyps: Where are we at in 2016?

It is currently known that colorectal cancers(CRC) arise from 3 different pathways: the adenoma to carcinoma chromosomal instability pathway(50%-70%); the mutator "Lynch syndrome" route(3%-5%); and the serrated pathway(30%-35%). The World Health Organization has classified serrated polyps into three types of lesions: hyperplastic polyps(HP),sessile serrated adenomas/polyps(SSA/P) and traditional serrated adenomas(TSA),the latter two strongly associated with development of CRCs. HPs do not cause cancer and TSAs are rare. SSA/P appear to be the responsible precursor lesion for the development of cancers through the serrated pathway. Both HPs and SSA/Ps appear morphologically similar. SSA/P are difficult to detect. The margins are normally inconspicuous. En bloc resection of these polyps can hence be troublesome. A careful examination of borders,submucosal injection of a dye solution(for larger lesions) and resection of a rim of normal tissue around the lesion may ensure total eradication of these lesions.     

Yield of screening colonoscopy in renal transplant candidates

BACKGROUND:

Cardiovascular disease is the most common cause of death among patients with end-stage renal disease undergoing maintenance dialysis. Renal transplantation offers a survival advantage to patients with end-stage renal disease; it is also associated with a three- to fivefold increase in the risk of developing a neoplasm.

OBJECTIVE:

To determine the yield of screening colonoscopy among patients with chronic kidney disease who were considered for renal transplantation.

METHODS:

Patients were included if they were ≥50 years of age, had chronic kidney disease and were being considered for renal transplantation. They underwent a screening colonoscopy that was performed as part of their pretransplant workup. Data from December 2008 to May 2014 were collected retrospectively for all eligible patients.

RESULTS:

During the study period, 433 patients were considered for renal transplantation. Of these, 170 underwent colonoscopies as part of their pretransplant workup. One was excluded because of previous history of colon cancer. Of the 169 procedures performed, ≥1 polyp(s) was diagnosed in 24%. The most common pathological diagnoses were hyperplastic polyp or normal colonic tissue. Fifteen (37%) patients had tubular adenomas and one patient had a sessile serrated adenoma. Advanced adenomas, defined as villous, tubulovillous or high-grade dysplasia, were found in four patients. Adenocarcinoma was diagnosed in one patient.

CONCLUSION:

In a population of asymptomatic potential kidney transplant recipients ≥50 years of age, the prevalence of colorectal adenomatous polyps was 24%. Colonoscopy appeared to be useful as a screening tool in potential transplant recipients.     

Molecular Profiling Based on <Emphasis Type="Italic">KRAS/BRAF</Emphasis> Mutation,Methylation, and Microsatellite Statuses in Serrated Lesions

Aim

The aim of your study is to characterize serrated lesions according to their molecular patterns, specifically BRAF/KRAS mutation, methylation, and microsatellite statuses. We evaluated the molecular patterns of 163 serrated lesions, including 37 microvesicular hyperplastic polyps, 73 sessile serrated adenomas/polyps (SSA/Ps), 31 traditional serrated adenomas, and 22 SSA/Ps with cytological dysplasia/adenocarcinoma.

Methods

Mutations in BRAF (V600E)/KRAS (exon 2) and microsatellite status [microsatellite stability (MSS) vs. MSI] were examined using a pyrosequencer and the PCR-based microsatellite method, respectively. DNA methylation status was classified as low (LME), intermediate (IME), or high methylation epigenotype (HME) according to a PCR-based two-step method. In addition, mucin and annexin A10 expression was examined. Finally, we performed a hierarchical clustering analysis of the BRAF/KRAS mutation, DNA methylation, and microsatellite statuses.

Results

The molecular patterns observed in the serrated lesions could be divided into five subgroups: lesions characterized by (1) BRAF mutation, HME, and MSI; (2) BRAF mutation, HME, and MSS; (3) BRAF mutation, LME/IME, and MSS; (4) no BRAF/KRAS mutations, LME/IME, and MSS; and (5) KRAS mutation, LME/IME, and MSS. In addition, we demonstrated that these observed molecular patterns help identify the associations of the molecular patterns and markers (i.e., mucin and annexin A10) with the clinicopathological findings, including histological features and histological diagnosis.

Conclusions

We suggest that the identified molecular patterns play an important role in the pathway of serrated lesion development.

     

Evaluation of magnifying colonoscopy in the diagnosis of serrated polyps

AIM: To elucidate the colonoscopic features of serrated lesions of the colorectum using magnifying colonoscopy.METHODS: Broad division of serrated lesions of the colorectum into hyperplastic polyps (HPs), traditional serrated adenomas (TSAs), and sessile serrated adenomas/polyps (SSA/Ps) has been proposed on the basis of recent molecular biological studies. However, few reports have examined the colonoscopic features of these divisions, including magnified colonoscopic findings. This study examined 118 lesions excised in our hospital as suspected serrated lesions after magnified observation between January 2008 and September 2011. Patient characteristics (sex, age), conventional colonoscopic findings (location, size, morphology, color, mucin) and magnified colonoscopic findings (pit pattern diagnosis) were interpreted by five colonoscopists with experience in over 1000 colonoscopies, and were compared with histopathological diagnoses. The pit patterns were categorized according to Kudo’s classification, but a more detailed investigation was also performed using the subclassification [type II-Open (type II-O), type II-Long (type II-L), or type IV-Serrated (type IV-S)] proposed by Kimura T and Yamano H.RESULTS: Lesions comprised 23 HPs (23/118: 19.5%), 39 TSAs (39/118: 33.1%: with cancer in one case), 50 SSA/Ps (50/118: 42.4%: complicated with cancer in three cases), and six others (6/118: 5.1%). We excluded six others, including three regular adenomas, one hamartoma, one inflammatory polyp, and one juvenile polyp for further analysis. Conventional colonoscopy showed that SSA/Ps were characterized as larger in diameter than TSAs and HPs (SSA/P vs HP, 13.62 ± 8.62 mm vs 7.74 ± 3.24 mm, P < 0.001; SSA/Ps vs TSA, 13.62 ± 8.62 mm vs 9.89 ± 5.73 mm, P < 0.01); common in the right side of the colon [HPs, 30.4% (7/23): TSAs, 20.5% (8/39): SSA/P, 84.0% (42/50), P < 0.001]; flat-elevated lesion [HPs, 30.4% (7/23): TSAs, 5.1% (2/39): SSA/Ps, 90.0% (45/50), P < 0.001]; normal-colored or pale imucosa [HPs, 34.8% (8/23): TSAs, 10.3% (4/39): SSA/Ps, 80% (40/50), P < 0.001]; and with large amounts of mucin [HPs, 21.7% (5/23): TSAs, 17.9% (7/39): SSA/Ps, 72.0% (36/50), P < 0.001]. In magnified colonoscopic findings, 17 lesions showed either type II pit pattern alone or partial type II pit pattern as the basic architecture, with 14 HPs (14/17, 70.0%) and 3 SSA/Ps. Magnified colonoscopy showed the type II-O pit pattern as characteristic of SSA/Ps [sensitivity 83.7% (41/49), specificity 85.7% (54/63)]. Cancer was also present in three lesions, in all of which a type VI pit pattern was also present within the same lesion. There were four HPs and four TSAs each. The type IV-S pit pattern was characteristic of TSAs [sensitivity 96.7% (30/31), specificity 89.9% (72/81)]. Cancer was present in one lesion, in which a type VI pit pattern was also present within the same lesion. In our study, serrated lesions of the colorectum also possessed the features described in previous reports of conventional colonoscopic findings. The pit pattern diagnosis using magnifying colonoscopy, particularly magnified colonoscopic findings using subclassifications of surface architecture, reflected the pathological characteristics of SSA/Ps and TSAs, and will be useful for colonoscopic diagnosis.CONCLUSION: We suggest that this system could be a good diagnostic tool for SSA/Ps using magnifying colonoscopy.     

Prevalence of Proximal Serrated Polyps and Conventional Adenomas in an Asymptomatic Average-Risk Screening Population

Background/Aims

Detection of proximal serrated polyps (PSPs) is increasingly recognized as a new qualitative target for colonoscopy. The aims of this study were to assess the detected prevalence of PSPs and synchronous adenomas in an asymptomatic average-risk screening cohort and to evaluate potential factors associated with detection of PSPs.

Methods

The study included 1,375 asymptomatic average-risk Korean patients (aged 50 years or older) who underwent screening colonoscopy. In total, 1,710 polyps were evaluated pathologically.

Results

The overall PSP detection rate (PSPDR) was low at 3.1%, despite high polyp (54.0%) and adenoma detection rates (ADRs, 43.5%). ADR did not correlate with PSPDR, but it was strongly correlated with PDR (r=0.810; p<0.001). Patients with PSPs were more likely to have longer withdrawal time and more proximal colon adenomas than patients without PSPs (adjusted odds ratio [OR], 1.19; 95% confidence interval [CI], 1.09 to 1.31; p<0.001) (adjusted OR, 2.03; 95% CI, 1.06 to 3.88; p=0.031, respectively).

Conclusions

The detected prevalence of PSPs was low (<5%) in an asymptomatic average-risk screening Korean population, despite the high prevalence of conventional adenomas. A longer mucosal inspection of the proximal colon may serve as a practical method to enhance detection of PSPs.     

Pancreaticoduodenectomy for advanced duodenal and ampullary adenomatosis in familial adenomatous polyposis

Background

Patients with familial adenomatous polyposis (FAP) develop duodenal and ampullary polyps that may progress to malignancy via the adenoma–carcinoma sequence.

Objective

The aim of this study was to review a large series of FAP patients undergoing pancreaticoduodenectomy for advanced duodenal and ampullary polyposis.

Methods

A retrospective case notes review of all FAP patients undergoing pancreaticoduodenectomy for advanced duodenal and ampullary adenomatosis was performed.

Results

Between October 1993 and January 2010, 38 FAP patients underwent pancreaticoduodenectomy for advanced duodenal and ampullary polyps. Complications occurred in 29 patients and perioperative mortality in two. Postoperative histology revealed five patients to have preoperatively undetected cancer (R = 0.518, P < 0.001).

Conclusions

Pancreaticoduodenectomy in FAP is associated with significant morbidity, but low mortality. All patients under consideration for operative intervention require careful preoperative counselling and optimization.     

Detection rate and proximal shift tendency of adenomas and serrated polyps: a retrospective study of 62,560 colonoscopies

Purpose

The purpose of this study is to estimate the detection rates of adenomas and serrated polyps and to identify proximalization and associate risk factors in patients from Southern China.

Methods

Consecutive patients undergoing colonoscopy from 2004 to 2013 in Guangzhou were included. The proportions of proximal adenomas to advanced adenomas and serrated polyps were compared and potential predictors were evaluated.

Results

Colonoscopies (n?=?62,560) were performed, and 11,427 patients were diagnosed with polyps. Detection rates for adenomas, hyperplastic polyps, and serrated adenomas were 12.0, 2.5, and 0.2 patients per 100 colonoscopies. When comparing the 1st (2004–2008) to the 2nd period (2009–2013), adenoma and serrated polyp detection in proximal and distal colon both increased significantly (proximal colon [adenoma 3.9 vs. 6.1 patients/100 colonoscopies, P?<?0.001; serrated polyp 0.4 vs. 1.1 patients/100 colonoscopies, P?<?0.001]; distal colon [adenoma 6.6 vs. 7.2 patients/100 colonoscopies, P?=?0.003; serrated polyp 1.2 vs. 2.4 patients/100 colonoscopies, P?<?0.001]). Advanced adenoma detection increased over these two periods only in proximal colon (1st vs. 2nd period: 1.5 vs. 2.4 patients/100 colonoscopies, P?<?0.001), not the distal colon (P?=?0.114). Multivariate analyses showed that diagnostic period was an independent predictor for adenoma proximalization (OR?=?1.36, 95% CI 1.25–1.48, P?<?0.001), but not for advanced adenomas (P?=?0.117) or serrated polyps (P?=?0.928).

Conclusions

Adenomas and serrated polyps were increasingly detected throughout the colon, whereas advanced adenomas were only in proximal colon. A proximal shift tendency detected by colonoscopy was observed for adenomas, but not advanced adenomas or serrated polyps, in Southern China. The screening for proximal polyps should be emphasized and colonoscopy might be a preferred initial screening tool.

     

Differential expression of p53 and p504s in hyperplastic polyp, sessile serrated adenoma and traditional serrated adenoma

Aims  

Known collectively as serrated polyps, hyperplastic polyps (HP), sessile serrated adenomas (SSA/SSP) and traditional serrated adenoma (TSA) may represent a spectrum of increasing malignant potential with characteristic immunological markers. There is increasing evidence that HP, SSA/SSP and TSA are biologically different and are likely to represent a spectrum along the serrated polyp pathway. Although there is general consensus about the diagnostic features of serrated polyps, the morphological differences between the categories are often subtle. This study compares the expression of p53 and P504S among serrated polyps. Sixty seven randomly selected biopsies (n = 59) and resection specimens (n = 8) histologically diagnosed for SSA/SSP, TSA and HP (19, 30 and 18 specimens, respectively) were obtained.     

Risk Factors for Incomplete Polyp Resection during Colonoscopic Polypectomy

Background/Aims

Colonoscopic polypectomy is highly efficient in preventing colorectal cancer, but polyps may not always be completely removed. Improved knowledge of the risk factors for incomplete polyp resection after polypectomy may decrease the cancer risk and additional costs. The aim of this study was to investigate the conditions that can cause incomplete polyp resection (IPR) after colonoscopic polypectomy.

Methods

A total of 12,970 polyps that were removed by colonoscopic polypectomy were investigated. Among them, we identified 228 cases with a positive resection margin and 228 controls with a clear resection margin that were matched for age, gender, and polyp size. We investigated the location, morphology, and histological type of the polyps and evaluated the skills of the endoscopist and assisting nurse.

Results

Multivariate analysis revealed that the polyps, which were located in the proximal part of the colon and rectum, were at significant risk of IPR. Histologically, an advanced polyp and an inexperienced assistant were also independent risk factors for IPR.

Conclusions

Polypectomy should be performed more carefully for polyps suspected to be cancerous and polyps located in the proximal part of the colon or rectum. A systematic training program for inexperienced assistants may be needed to decrease the risk of IPR.     

Cost-effectiveness of various diagnostic approaches for occupational asthma

BACKGROUND:

Diagnosis of occupational asthma (OA) by specific inhalation challenge (SIC) can be costly and is not always available. The use of sputum testing to avoid this in some patients may be a more cost-effective alternative.

OBJECTIVES:

To compare the cost-effectiveness of SIC with serial measurements of sputum cell counts (sputum testing) and peak expiratory flow (PEF) monitoring.

METHODS:

Clinical data and testing costs for OA in 49 patients were collected during a previously published trial, modelled and compared using TreeAge Pro. Clinical outcome was the percentage of accurately diagnosed patients, using SIC as the gold standard. The PEF approach used the most accurate assessment of five experts who were blinded to SIC results. Differences in the proportion of eosinophils during periods on and off work were used for the sputum testing approach and in PEF/sputum for the combined approach. Unit costs were estimated from charges in Canadian hospitals. Data were analyzed by one-way and two-way analyses, and by probabilistic sensitivity analysis using a Monte Carlo simulation technique.

RESULTS:

The PEF approach had an estimated accuracy of 52% and cost $365 per patient tested. Compared with PEF monitoring, sputum testing was more accurate and cost an estimated $255 for each additional OA patient correctly diagnosed. SIC costs per additional correct diagnosis were $11,032 compared with sputum testing and $6,458 compared with PEF monitoring. The combined PEF/sputum testing approach was not cost-effective in the base case analysis, but cannot be excluded according to probabilistic sensitivity analyses.

CONCLUSIONS:

Although SIC remains the reference test to diagnose OA, when this test is not available, sputum testing is a cost-effective alternative to PEF for diagnosis of OA.     

The utility of a portable sleep monitor to diagnose sleep-disordered breathing in a pediatric population

BACKGROUND:

Central and/or obstructive sleep-disordered breathing (SDB) in children represents a spectrum of abnormal breathing during sleep. SDB is diagnosed using the gold standard, overnight polysomnography (PSG). The limited availability and access to PSG prevents its widespread use, resulting in significant delays in diagnosis and treatment of SDB. As such, portable sleep monitors are urgently needed.

OBJECTIVE:

To evaluate the utility of a commercially available portable sleep study monitor (PSS-AL) (ApneaLink, ResMed, USA) to diagnose SDB in children.

METHODS:

Children referred to a pediatric sleep facility were simultaneously monitored using the PSS-AL monitor and overnight PSG. The apnea-hypopnea index (AHI) was calculated using the manual and autoscoring function of the PSS-AL, and PSG. Sensitivity and specificity were compared with the manually scored PSS-AL and PSG. Pearson correlations and Bland-Altman plots were constructed.

RESULTS:

Thirty-five children (13 female) completed the study. The median age was 11.0 years and the median body mass index z-score was 0.67 (range −2.3 to 3.8). SDB was diagnosed in 17 of 35 (49%) subjects using PSG. The AHI obtained by manually scored PSS-AL strongly correlated with the AHI obtained using PSG (r=0.89; P<0.001). Using the manually scored PSS-AL, a cut-off of AHI of >5 events/h had a sensitivity of 94% and a specificity of 61% to detect any SDB diagnosed by PSG.

CONCLUSIONS:

Although PSG is still recommended for the diagnosis of SDB, the ApneaLink sleep monitor has a role for triaging children referred for evaluation of SDB, but has limited ability to determine the nature of the SDB.     

Role of enhanced visibility in evaluating polyposis syndromes using a newly developed contrast image capsule endoscope

Background/Aims

A flexible spectral imaging color enhancement system was installed in new capsule software for video capsule endoscopy. Contrast image capsule endoscopy (CICE) is a novel technology using light-emitting diodes selected for the main absorption range of hemoglobin. We assessed the feasibility and diagnostic effi cacy for small bowel surveillance in patients with polyposis syndromes.

Methods

Six patients with polyposis syndromes, four with familial adenomatous polyposis and one each with Cowden syndrome (CS) and Cronkhite-Canada syndrome (CCS) were examined using CICE. We conducted three evaluations to assess the effect on the numbers of the detected polyps; compare polyp diagnostic rates between adenoma and hamartoma; and assess polyp visibility.

Results

The numbers of detected polyps and diagnostic accuracy did not differ signifi cantly between pre-contrast and contrast images. However, 50% of the adenomatous polyps displayed enhanced visibility on contrast images. CICE contrast images exhibited clearly demarcated lesions and improved the visibility of minute structures of adenomatous polyps. Hamartomatous polyp micro-structures in patients with CS and CCS were more clearly visualized on contrast than pre-contrast images.

Conclusions

CICE is an effective tool for enhancing the visibility of polyps in patients with polyposis syndrome.     

Visceral Obesity If Associated with Gallbladder Polyps

Background/Aims

Gallbladder polyps (GBP) are a common clinical finding and may possess malignant potential. We conducted this study to determine whether visceral obesity is a risk factor for GBP.

Methods

We retrospectively reviewed records of subjects who received both ultrasonography and computed tomography with measurements of the areas of visceral adipose tissue and total adipose tissue (TAT) on the same day as health checkups.

Results

Ninety-three of 1,615 subjects (5.8%) had GBP and were compared with 186 age- and sex-matched controls. VAT (odds ratio [OR], 2.941; 95% confidence interval [CI], 1.325 to 6.529; p=0.008 for the highest quartile vs the lowest quartile) and TAT (OR, 3.568; 95% CI, 1.625 to 7.833; p=0.002 for the highest quartile vs the lowest quartile) were independent risk factors together with hypertension (OR, 2.512; 95% CI, 1.381 to 4.569; p=0.003), diabetes mellitus (OR, 2.942; 95% CI, 1.061 to 8.158; p=0.038), hepatitis B virus positivity (OR, 3.548; 95% CI, 1.295 to 9.716; p=0.014), and a higher level of total cholesterol (OR, 2.232; 95% CI, 1.043 to 4.778; p=0.039 for <200 mg/dL vs ≥240 mg/dL). Body mass index and waist circumference were not meaningful variables.

Conclusions

Visceral obesity measured by VAT and TAT was associated with GBP irrespective of body mass index or waist circumference.