Detection and analysis of serum bile acid profile in patients with colonic polyps

BACKGROUND Analyzing the variations in serum bile acid(BA)profile can provide a certain biological basis for early warning and prevention of various diseases.There is currently no comprehensive study on the relationship between the serum BA profile and colonic polyps.AIM To study the serum BA profile detection results of patients with colonic polyps,and analyze the correlation between BA and colonic polyps.METHODS From January 1,2022,to June 1,2023,204 patients with colonic polyps who were diagnosed and treated at Zhongda Hospital Southeast University were chosen as the study subjects,and 135 non-polyp people who underwent physical examination were chosen as the control group.Gathering all patients'clinical information,typical biochemical indicators,and BA profile.RESULTS Compared with the control group,the serum levels of taurocholic acid,glycocholic acid,glycochenodeoxycholic acid,and taurochenodeoxycholic acid in the colonic polyp group were significantly higher than those in the control group,while the content of deoxycholic acid(DCA)was lower than that in the control group(P<0.05).When colonic polyps were analyzed as subgroups,it was shown that there was a strong correlation between changes in the BA profile and polyp diameter,location,morphology,pathological kind,etc.CONCLUSION The serum BA profile showed significant changes in patients with colonic polyps,with a significant increase in primary conjugated BA content and a decrease in secondary free bile acid DCA content.There is a certain correlation between primary free BA and pathological parameters of polyps.

Colonic schistosomiasis mimicking cancer,polyp,and inflammatory bowel disease:Five case reports and review of literature

BACKGROUND Schistosomiasis,officially named as a neglected tropical disease by The World Health Organization,is a serious parasitic disease caused by trematode flukes of the genus Schistosoma.It is a common infectious disease,endemic in more than 78 countries.The disease can involve various organs and poses far-reaching public health challenges.CASE SUMMARY Here,we present a series of five patients with variable presentations:an asymptomatic patient who was diagnosed with colonic schistosomiasis upon screening colonoscopy;2 patients with clinical suspicion of colonic cancer;and 2 patients with a clinical diagnosis of inflammatory bowel disease.All patients were subsequently confirmed to have colonic schistosomiasis after colonoscopy and histopathologic examination.The clinical manifestations,colonoscopy features and histologic findings of the patients are described.Most of the patients showed significant clinical improvement following administration of oral praziquantel.CONCLUSION Intestinal schistosomiasis can present with features mimicking other gastrointestinal conditions.This disease should be a diagnostic consideration in patients who live in or have traveled to endemic areas.

Jumbo biopsy is useful for the diagnosis of colonic prolapsing mucosal polyps with diverticulosis

We report here a case of multiple prolapsing mucosal polyps with diverticulosis in the sigmoid colon. A 52-year- old man was admitted to our hospital because of bloody diarrhea. Colonoscopy and barium enema showed multiple diverticula, markedly thickened mucosal folds and polypoid lesions with mucus on the top of them in the sigmoid colon. Endoscopic ultrasonography showed thickening of the mucosal and submucosal layers. Several endoscopic biopsy specimens were taken from the polypoid lesions. Histological examination revealed only chronic inflammatory cell infiltration. In order to obtain a definite diagnosis, we performed endoscopic jumbo biopsy for the polypoid lesions after obtaining informed consent. Histological examination revealed marked lymphocyte infiltration, hemosiderin deposits and fibromuscular obliteration in the lamina propria, features similar to those of mucosal prolapsing syndrome. After anti-diarrhetic treatment, clinical findings were improved. Thus, jumbo biopsy is useful for diagnosis and treatment of prolapsing mucosal polyps.

Application of Computed Tomographic Colonography in Diagnosis of Colonic Polyps

Objective To assess the clinical values of computed tomographic colonography （CTC） in diagnosis of colonic polyps. Methods Forty-two patients who were clinically suspicious of colonic polyps or underwent colonic polyps screening received examinations with both CTC and conventional colonoscopy. Sixteen- or 64-slice spiral computed tomography and professional imaging processing techniques were used for evaluation. Per-polyp and per-patient results were analyzed. Those by per-polyp were subsequently divided into ≥10 mm group, 5-10 mm group, and ≤5 mm group. Sensitivity, positive predictive value （PPV）, specificity, negative predictive value （NPV）, and accuracy were calculated using statistical method for diagnostic studies, with conventional colonoscopy as a gold standard. Results Ninety and 61 polyps were found by CTC and conventional colonoscopy, respectively. The per-polyp sensitivity/PPV were 80.3%/55.6% in total, and 100%/92.9%, 93.8%/65.2%, and 68.8%/ 41.5% in the ≥10 mm group, 5-10 mm group, and ≤5 turn group, respectively. The per-patient sensitivity, PPV, specificity, NPV, and accuracy were 97.1%, 89.5%, 42.9%, 75.0%, and 88.1%, respectively. Conclusion CTC can clearly reveal the morphology of colonic polyps and be used as a routine monitoring method for the clinical diagnosis of polyps.

Predictive factors and model validation of post-colon polyp surgery Helicobacter pylori infection

BACKGROUND Recently,research has linked Helicobacter pylori(H.pylori)stomach infection to colonic inflammation,mediated by toxin production,potentially impacting colorectal cancer occurrence.AIM To investigate the risk factors for post-colon polyp surgery,H.pylori infection,and its correlation with pathologic type.METHODS Eighty patients who underwent colon polypectomy in our hospital between January 2019 and January 2023 were retrospectively chosen.They were then randomly split into modeling(n=56)and model validation(n=24)sets using R.The modeling cohort was divided into an H.pylori-infected group(n=37)and an H.pylori-uninfected group(n=19).Binary logistic regression analysis was used to analyze the factors influencing the occurrence of H.pylori infection after colon polyp surgery.A roadmap prediction model was established and validated.Finally,the correlation between the different pathological types of colon polyps and the occurrence of H.pylori infection was analyzed after colon polyp surgery.RESULTS Univariate results showed that age,body mass index(BMI),literacy,alcohol consumption,polyp pathology type,high-risk adenomas,and heavy diet were all influential factors in the development of H.pylori infection after intestinal polypectomy.Binary multifactorial logistic regression analysis showed that age,BMI,and type of polyp pathology were independent predictors of the occurrence of H.pylori infection after intestinal polypectomy.The area under the receiver operating characteristic curve was 0.969[95%confidence interval(95%CI):0.928–1.000]and 0.898(95%CI:0.773–1.000)in the modeling and validation sets,respectively.The slope of the calibration curve of the graph was close to 1,and the goodness-of-fit test was P>0.05 in the two sets.The decision analysis curve showed a high rate of return in both sets.The results of the correlation analysis between different pathological types and the occurrence of H.pylori infection after colon polyp surgery showed that hyperplastic polyps,inflammatory polyps,and the occurrence of H.pylori infection were not significantly correlated.In contrast,adenomatous polyps showed a significant positive correlation with the occurrence of H.pylori infection.CONCLUSION Age,BMI,and polyps of the adenomatous type were independent predictors of H.pylori infection after intestinal polypectomy.Moreover,the further constructed column-line graph prediction model of H.pylori infection after intestinal polypectomy showed good predictive ability.

Schistosomal(bilharzial)polyps:Travel through the colon and beyond

Schistosomiasis(bilharziasis)is a major neglected tropical disease.It is endemic in many tropical and subtropical communities.Schistosomal polyps(S.polyps)are not uncommon presentation of this infection.Although the colon is the most commonly affected organ,many other organs are affected.S.polyps are associated with a variable range of morbidity independent of the Schistosomal infection.S.polyps are frequently described in endemic areas and increasingly reported in non-endemic areas mainly among immigrants and visitors to the endemic areas.This review aimed to increase awareness of practitioners,especially gastroenterologists,for this peculiar type of polyps caused by this neglected infection hence improving patient outcomes.Web-based search of different databases was conducted for the literature focusing the development of S.polyps in the colon and other organs with analysis of the clinical manifestations,diagnosis and treatment.The following key words were used in the search,“Schistosomiasis”OR“Bilharziasis”AND“Polyps”OR“Polyp”AND“Colon”OR“Small intestine”OR“Duodenum”OR“Stomach”OR“Esophagus”OR”Gallbladder”OR”Pharynx”OR“Larynx”OR“Trachea”OR”Urinary bladder”OR“Ureter”OR“Renal Pelvis”OR“Urethra”.All publication types including case reports,case series,original research,and review articles were retrieved and analyzed.S.polyps are not infrequent presentation of acute or chronic Schistosomal infection.S.polyps are described in many organs including the bowel,genitourinary tract,skin,gallbladder and the larynx.Presentation of S.polyps is variable and depends on the site,number as well as the polyp size.The relationship of S.polyps to malignant transformation is a matter of discussion.Presence of S.polyps is sometimes the only manifestation of Schistosomiasis.Small polyps can be treated medically with praziquantel,while large accessible polyps are amendable for endoscopic excision through different polyp resection techniques.However,huge,complicated,non-accessible and suspicious polyps are indicated for surgical management or advanced endoscopic resection when appropriate.Clinicians and endoscopists should be aware about these facts when treating patients living in,immigrated from or visiting endemic areas.

Cold snare polypectomy:A closer look at the efficacy and limitations for polyps 10-20 mm in size

Current guidelines recommend cold snare polypectomy for polyps less than 10 mm in size.Conversely,endoscopic mucosal resection is still the preferred technique for larger polyps.Concerns regarding cold snare polypectomy for larger polyps revolve around the difficulty in conducting en-bloc resection(resulting in piecemeal removal),and the potential for local residual polyp tissue and a high rate of recurrence.On the other hand,cold snare technique has the advantages of shortening procedure time,reducing delayed bleeding risks and lowering cost of treatment.Numerous ongoing and recent studies are focused on evaluating the risks and benefits of this technique for polyps larger than 10 mm,with the goal of providing clear guidelines in the near future.The aim of this editorial is to provide our readers with an overview regarding this subject and the latest developments surrounding it.

Automated Colonic Polyp Detection and Classification Enabled Northern Goshawk Optimization with Deep Learning

The major mortality factor relevant to the intestinal tract is the growth of tumorous cells(polyps)in various parts.More specifically,colonic polyps have a high rate and are recognized as a precursor of colon cancer growth.Endoscopy is the conventional technique for detecting colon polyps,and considerable research has proved that automated diagnosis of image regions that might have polyps within the colon might be used to help experts for decreasing the polyp miss rate.The automated diagnosis of polyps in a computer-aided diagnosis(CAD)method is implemented using statistical analysis.Nowadays,Deep Learning,particularly throughConvolution Neural networks(CNN),is broadly employed to allowthe extraction of representative features.This manuscript devises a new Northern Goshawk Optimization with Transfer Learning Model for Colonic Polyp Detection and Classification(NGOTL-CPDC)model.The NGOTL-CPDC technique aims to investigate endoscopic images for automated colonic polyp detection.To accomplish this,the NGOTL-CPDC technique comprises of adaptive bilateral filtering(ABF)technique as a noise removal process and image pre-processing step.Besides,the NGOTL-CPDC model applies the Faster SqueezeNet model for feature extraction purposes in which the hyperparameter tuning process is performed using the NGO optimizer.Finally,the fuzzy Hopfield neural network(FHNN)method can be employed for colonic poly detection and classification.A widespread simulation analysis is carried out to ensure the improved outcomes of the NGOTL-CPDC model.The comparison study demonstrates the enhancements of the NGOTL-CPDC model on the colonic polyp classification process on medical test images.

Association between CYP24A1 polymorphisms and the risk of colonic polyps and colon cancer in a Chinese population

AIM To determine the pathogenesis and potential single nucleotide polymorphisms(SNPs) as screening sites for colonic polyps,colon cancer and ulcerative colitis,and to analyze the possible association between these genetic polymorphisms and the three diseases. METHODS We evaluated genetic polymorphisms in 144 newly diagnosed colonic polyp patients,96 colon cancer patients and 44 ulcerative colitis patients. The four SNPs genotyped were rs4809957,rs6068816,rs6091822 and rs8124792. The control group consisted of 504 East Asians enrolled in the 1000 Genomes Project. Correlations between CYP24A1 SNPs and the diseases were analyzed by Fisher's exact probability test.RESULTS CYP24A1 polymorphisms rs4809957 A/G and rs6068816 C/T showed a statistically significant association with risk of the three diseases,when both the genotypes and allele frequencies were considered. With regard to rs6091822 G/T,all three diseases were related to risk allele carriers(GT + TT) vs wild-type(GG),but the associations between the allele frequencies and the diseases were not significant. The risk of colonic polyps and colon cancer was related to the allele frequencies of rs8124792 G/A,and this association remained for genotype frequencies of this SNP. CONCLUSION Four SNPs are related to the risk of colonic polyps and colon cancer. G allele in rs6091822 G/T may play an anti-cancer role only if it is homozygous. The A allele,which is a minor component of rs8124792,may be indicated in the diagnosis of colonic polyps or colon cancer rather than ulcerative colitis.

Prevalence of advanced colonic polyps in asymptomatic Chinese

AIM: To investigate the prevalence of advanced polyps in asymptomatic Chinese and to determine the risk of proximal advanced colonic polyps in subjects with and without polyps in the distal colon.METHODS: Data were collected prospectively during colonoscopic examinations performed in 5 973 subjects as part of health evaluation at our unit from December 1997 to December 2003. Polyps were considered advanced, if they were larger than 10 mm or were tubovillous, villous or malignant. Proximal colon was defined as the splenic flexure and more proximal portions of the colon.RESULTS: Colon polyps were detected in 971 (16.3%)subjects (613 males and 358 females) with their mean age being 56.6±10.7 years. Advanced polyps were noted in 199 (3.3%) individuals. Subjects were sub-classified according to the location of polyps into three groups: distal (569, 58.6%), proximal (284, 29.2%), and combined proximal and distal (118, 12.2%) groups. Subjects with advanced polyps in these three groups were 95 (9.8%),56 (5.8%), and 48 (4.9%) respectively. In the 48 subjects with advanced combined polyps, 13 advanced polyps were distributed at the distal colon, 17 at the proximal colon,and 18 at both. Eighteen colon cancers including 12 at sigmoid and 6 at ascending colon were confirmed by final pathology. The relative risk for advanced proximal polyp according to distal findings was 3.1 (95%CI: 1.3-7.4) for hyperplastic polyp, 2.7 (95%CI: 1.4-5.3) for tubular polyp and 13.5 (95%CI: 5.1-35.4) for advanced polyp as compared to that for no polyp. However, 56 (28.2%) of 199 subjects with advanced polyps had no index polyps at the distal colon and might go undetected under sigmoidoscopic screening.CONCLUSION: Although distal lesions can predict the risk of advanced proximal polyps, a substantial portion of Chinese with advanced proximal polyps is not associated with any distal sentinel lesions. These data have implications for screening policy of colon cancers in Taiwan Residents Chinese.

Colonic polyps: Is it useful to characterize them with advanced endoscopy?

There have been major developments in endoscopic imaging techniques in recent years.Endoscopes with high definition and magnification can provide high quality images that allow for the histological estimation of lesions in vivo and in situ when combined with ancillary enhancement techniques such as chromoendoscopy(CE)and virtual CE(narrow band imaging fujinon intelligent chromoendoscopy,or i-Scan).Despite the enormous potential for these advanced techniques,their value and feasibility in the clinic are still doubted,particularly in cases of colonic polyps that are slated for removal,where in vivo characterization may be deemed unnecessary.However,there are several advantages offered by such advanced endoscopic imaging.CE with or without magnification demonstrates highly accurate histology and invasion depth prediction,and virtual CE is a feasible and less cumbersome alternative to CE in terms of histological estimation,though not sufficiently accurate for depth invasion prediction.Furthermore,the supplementary information provided by advanced imaging systems can assist the endoscopist in the selection of a strategic approach,such as in deciding whether a colonic lesion should be resected,left in situ,or requires more intensive surgical treatment.Lastly,advanced high-resolution imaging techniques may be more cost effective,such that histopathology of lowrisk lesions following resection can be eliminated.The results of these evaluations and comparisons with traditional CE are presented and discussed.Taken together,the benefits provided by these advanced capabilities justify their development,and advocates their use for the treatment and management of colonic polyps.

Management of local recurrence after endoscopic resection of neoplastic colonic polyps

A proportion of neoplastic polyps are incompletely resected, resulting in local recurrence, especially after resection of large polyps or piecemeal resection. Local recurrences that develop after endoscopic resection of intramucosal neoplasms that lacked risk factors for lymph node metastasis or positive vertical margins are usually treated endoscopically. Endoscopic submucosal dissection(ESD) is indicated for local residual or recurrent early carcinomas after endoscopic resection. However, ESD for such recurrent lesions is technically difficult and is typically a lengthy procedure. Underwater endoscopic mucosal resection(UEMR), which was developed in 2012, is suitable for recurrent or residual lesions and reportedly achieves superior en bloc resection rates and endoscopic complete resection rates than conventional EMR. However, a large recurrent lesion is a negative independent predictor of successful en bloc resection and of complete endoscopic removal. We therefore perform UEMR for relatively small(≤ 10-15 mm) recurrent lesions and ESD for larger lesions.

High-definition colonoscopy with i-Scan:Better diagnosis for small polyps and flat adenomas

AIM： To investigate if high-definition （HD） colonoscope with i-Scan gave a higher detection rate of mucosal le- sions vs standard white-light instruments. METHODS： Data were collected from the computer- ized database of the endoscopy unit of our tertiary referral center. We retrospectively analyzed 1101 con- secutive colonoscopies that were performed over 1 year with standard white-light （n = 849） or HD＋ with i-Scan （n = 252） instruments by four endoscopists, in an outpatient setting. Colonoscopy records included patients＇ main details and family history for colorectal cancer, indication for colonoscopy （screening, diagnos- tic or surveillance）, type of instrument used （standard white-light or HD＋ plus i-Scan）, name of endoscopist and bowel preparation. Records for each procedure included whether the cecum was reached or not and the reason for failure, complications during or imme- diately after the procedure, and number, size, location and characteristics of the lesions. Polyps or protruding lesions were defined as sessile or pedunculated, and nonprotruding lesions were defined according to Paris classification. For each lesion, histological diagnosis was recorded. RESULTS： Eight hundred and forty-nine colonosco- pies were carried with the standard white-light video colonoscope and 252 with the HD＋ plus i-Scan video colonoscope, The four endoscopists did 264, 300, 276 and 261 procedures, respectively; 21.6%, 24.0%, 21.7% and 24.1% of them with the HD＋ plus i-Scan technique. There were no significant differences be- tween the four endoscopists in either the number of procedures done or the proportions of each imaging technique used. Both techniques detected one or more mucosal lesions in 522/1101 procedures （47.4%）. The overall number of lesions recognized was 1266; 645 in the right colon and 621 in the left. A significantly higher number of colonoscopies recognized lesions in the HD＋ plus i-Scan mode （171/252 = 67.9%） than with the standard white-light technique （408/849 = 48.1%） （P 〈 0.0001）. HD＋ with i-Scan colonoscopies identified more lesions than standard white-light imag- ing （459/252 and 807/849, P 〈 0.0001）, in the right or left colon （mean ：1： SD, 1.62±1.36 vs 1.33±0.73, P 〈 0.003 and 1.55±0.98 vs 1.17±0.93, P = 0.033）, more lesions 〈 10 mm （P 〈 0.0001） or nonprotruding （P 〈 0.022）, and flat polyps （P = 0.04）. The cumulative mean number of lesions per procedure detected by the four endoscopists was significantly higher with HD＋ with i-Scan than with standard white-light imaging （1.82 ± 2.89 vs 0.95± 1.35, P 〈 0.0001）. CONCLUSION： HD imaging with i-Scan during the withdrawal phase of colonoscopy significantly increased the detection of colonic mucosal lesions, particularly small and nonprotruding polyps.

Comparative effectiveness of i-SCAN^(TM) and high-definition white light characterizing small colonic polyps

AIM： To evaluate accuracy of in vivo diagnosis of ad- enomatous vs non-adenomatous polyps using/-SCAN digital chromoendoscopy compared with high-definition white light. METHODS： This is a single-center comparative effec- tiveness pilot study. Polyps （n = 103） from 75 average- risk adult outpatients undergoing screening or surveil- lance colonoscopy between December 1, 2010 and April 1, 2011 were evaluated by two participating en- doscopists in an academic outpatient endoscopy center. Polyps were evaluated both with high-definition white light and with/-SCAN to make an/n vivo prediction of adenomatous vs non-adenomatous pathology. We de- termined diagnostic characteristics of/-SCAN and high- definition white light, including sensitivity, specificity, and accuracy, with regards to identifying adenomatous vs non-adenomatous polyps. Histopathologic diagnosis was the gold standard comparison. RESULTS： One hundred and three small polyps, de- tected from forty-three patients, were included in the analysis. The average size of the polyps evaluated in the analysis was 3.7 mm （SD 1.3 mm, range 2 mm to 8 mm）. Formal histopathology revealed that 54/103 （52.4%） were adenomas, 26/103 （25.2%） were hyper- plastic, and 23/103 （22.3%） were other diagnoses in- clude ＂lymphoid aggregates＂, ＂non-specific colitis,＂ and ＂no pathologic diagnosis.＂ Overall, the combined accu- racy of endoscopists for predicting adenomas was iden- tical between/-SCAN （71.8%, 95%CI： 62.1%-80.3%） and high-definition white light （71.8%, 95%CI： 62.1%-80.3%）. However, the accuracy of each endosco- pist differed substantially, where endoscopist A demon- strated 63.0% overall accuracy （95%CI： 50.9%-74.0%） as compared with endoscopist B demonstrating 93.3% overall accuracy （95%CI： 77.9%-99.2%）, irrespective of imaging modality. Neither endoscopist demonstrated a significant learning effect with i-SCAN during the study. Though endoscopist A increased accuracy using/-SCAN from 59% （95%CI： 42.1%-74.4%） in the first half to 67.6% （95%CI： 49.5%-82.6%） in the second half, and endoscopist B decreased accuracy usingi-SCAN from 100% （95%CI： 80.5%-100.0%） in the first half to 84.6% （95%CI： 54.6%-98.1%） in the second half, nei- ther of these differences were statistically significant. CONCLUSION：i-SCAN and high-definition white light had similar efficacy predicting polyp histology. Endosco- pist training likely plays a critical role in diagnostic test characteristics and deserves further study.

Association between colonic polyps and diverticular disease

AIM: To evaluate the association between colonic polyps and diverticular disease in Japan. METHODS: We retrospectively reviewed the medical records of 672 consecutive patients who underwent total colonoscopy between August 2006 and April 2007 at Nishinjo Hospital, Okinawa, Japan. Patients with a history of any of the following were excluded from the study: previous polypectomy, colonic resection, and inflammatory bowel diseases. The association between colonic polyps and diverticular disease was analyzed by logistic regression analysis, adjusted for age and sex. RESULTS: Prevalence of colonic polyps in all patients with diverticular disease was significantly higher than that in those without diverticular disease (adjusted odds ratio 1.7). CONCLUSION: Our data showed that patients with diverticular disease have a higher risk of colonic polyps compared to those without.

BRAF inhibitor treatment of melanoma causing colonic polyps:An alternative hypothesis

Colonic polyps may arise from BRAF inhibitor treatment of melanoma, possibly due to paradoxical activation of the mitogen-activated protein (MAP)-kinase pathway. In an alternative evidence based scenario, tubular colonic adenomas with APC gene mutations have also been identified in the context of BRAF inhibitor treatment, in the absence of mutations of MAPK genes. A minority of colorectal cancers develop by an alternative “serrated polyp pathway”. This article postulates a novel hypothesis, that the established phenotypic and molecular characteristics of serrated colonic polyps/CRC offer an intriguing insight into the pathobiology of BRAF inhibitor induced colonic polyps. Serrated polyps are characterized by a CpG island methylation phenotype, MLH1 silencing and cellular senescence. They also have BRAF mutations. The contention is that BRAF inhibitor induced polyps mimic the afore-described histology and molecular features of serrated polyps with the exception that instead of the presence of BRAF mutations they induce C-RAF homodimers and B-RAF: C-RAF heterodimers.

Can optical diagnosis of small colon polyps be accurate? Comparing standard scope without narrow banding to high definition scope with narrow banding

AIM: To study the accuracy of using high definition(HD) scope with narrow band imaging(NBI) vs standard white light colonoscope without NBI(ST), to predict the histology of the colon polyps, particularly those < 1 cm.METHODS: A total of 147 African Americans patients who were referred to Howard University Hospital for screening or, diagnostic or follow up colonoscopy, during a 12-mo period in 2012 were prospectively recruited. Some patients had multiple polyps and total number of polyps was 179. Their colonoscopies were performed by 3 experienced endoscopists who determined the size and stated whether the polyps being removed were hyperplastic or adenomatous polyps using standard colonoscopes or high definition colonoscopes with NBI. The histopathologic diagnosis was reported by pathologists as part of routine care. RESULTS: Of participants in the study, 55(37%) were male and median(interquartile range) of age was 56(19-80). Demographic, clinical characteristics, past medical history of patients, and the data obtained by two instruments were not significantly different and two methods detected similar number of polyps. In ST scope 89% of polyps were < 1 cm vs 87% in HD scope(P = 0.7). The ST scope had a positive predictive value(PPV) and positive likelihood ratio(PLR) of 86% and 4.0 for adenoma compared to 74% and 2.6 for HD scope. There was a trend of higher sensitivity for HD scope(68%) compare to ST scope(53%) with almost the same specificity. The ST scope had a PPV and PLR of 38% and 1.8 for hyperplastic polyp(HPP) compared to 42% and 2.2 for HD scope. The sensitivity and specificity of two instruments for HPP diagnosis were similar.CONCLUSION: Our results indicated that HD scope was more sensitive in diagnosis of adenoma than ST scope. Clinical diagnosis of HPP with either scope is less accurate compared to adenoma. Colonoscopy diagnosis is not yet fully matched with pathologic diagnosis of colon polyp. However with the advancement of both imaging and training, it may be possible to increase the sensitivity and specificity of the scopes and hence save money for eliminating time and the cost of Immunohistochemistry/pathology.

Endoscopic mucosal ablation-an alternative treatment for colonic polyps:Three case reports

BACKGROUND Endoscopic resection of non-invasive lesions is now the standard of care for lesions in the GI tract.However,resection techniques require extensive training,are not available in all endoscopy centers and are prone to complications.Endoscopic mucosal ablation(EMA)is a combination of resection and ablation techniques and it may offer an alternative in the management of such lesions.CASE SUMMARY In this case series we report the successful treatment of three flat colonic polyps using the EMA technique.Two lesions were treatment naïve and 1 was a recurrence after an endoscopic mucosal resection.The sizes ranged from 2 to 4 cm.All three polyps were ablated successfully with no immediate or delayed complications.The recurrence rate at 1 year of follow up was 0%.CONCLUSION Based on this initial experience,we conclude that EMA is a safe and effective technique for the treatment of non-invasive colonic polyps when endoscopic resection techniques are not available.

Increasing prevalence of advanced colonic polyps in young patients undergoing colonoscopy in a referral academic hospital in Hong Kong

AIM： To investigate the distribution and frequency of advanced polyps over eight years.METHODS：6424 colonoscopies were reviewea aunng the study period 1998 to 2005. The study period was subdivided into period I ： 1998 to 2001 and period 11： 2002-2005. RESULTS： 1856 polyps （33% advanced polyps） and 328 CRCs were detected. The mean ages of the patients with advanced polyps and cancer were 69.2 ± 12.0 and 71.6± 13.8 years, respectively. Advanced polyps were mainly lerc sided （59.5%）. Advanced polyps were found in patients ≤60 years from 17.7% in period Ⅰto 26.3% in period Ⅱ（P 〈 0.05）, especially in male subjects ≤60 years （21.6% vs 31.6%, P 〈 0.05）. Advanced tubuloviUous polyps rose from 21.5% in period I to 29.5% in period Ⅱ （P 〈 0.05）. Whereas cancers in male patients ≤ 60 years were similar in both periods： 23.2% vs 16.5% （P 〉 0.05）.CONCLUSION： Advanced polyps increased significantly in the younger male group in the most recent period and there seems to be a shiE towards a proximal location.

Diagnostic value of high-resolution micro-endoscopy for theclassification of colon polyps

AIM: To study a new imaging equipment, highresolution micro-endoscopy(HRME), in the diagnosis and pathological classification of colon polyps.METHODS: We selected 114 specimens of colon polyps, 30 of which were colon polyps with known pathological types and 84 that were prospective polyp specimens; 10 normal colon mucosa specimens served as controls. We obtained images of 30 colon polyp specimens with known pathological types using HRME and analyzed the characteristics of these images to develop HRME diagnostic criteria for different pathological types of colon polyps. Based on these criteria, we performed a prospective study of 84 colon polyp specimens using HRME and compared the results with those of the pathological examination to evaluate the diagnostic value of HRME in the pathological classification of different types of colon polyps. RESULTS: In the 30 cases of known pathological type of colon polyp samples, there were 21 cases of adenomatous polyps, which comprised nine cases of tubular adenoma, seven cases of villous adenoma and five cases of mixed adenomas. The nine cases of non-adenomatous polyps included four cases of inflammatory polyps and five cases of hyperplastic polyps five. Ten cases of normal colonic mucosa were confirmed pathologically. In a prospective study of 84 cases using HRME, 23 cases were diagnosed as inflammatory polyps, 11 cases as hyperplastic polyps, 18 cases as tubular adenoma, eight cases as villous adenoma and 24 cases as mixed adenomas. After pathological examination, 24 cases were diagnosed as inflammatory polyps, 11 cases as hyperplastic polyps, 19 cases as tubular adenoma, eight cases as villous adenoma and 22 cases as mixed adenomas. Compared with the pathological examinations, the sensitivities, specificities, accuracies, and positive and negative predictive values of HRME in diagnosing inflammatory polyps(87.5%, 96.7%, 94.0%, 91.3% and 95.1%), hyperplastic polyps(72.7%, 95.9%, 92.9%, 72.7% and 95.9%), tubular adenomas(73.7%, 93.8%, 89.3%, 77.8% and 92.4%), villous adenomas(75.0%, 97.4%, 95.2%, 75.0% and 97.4%), and mixed adenomas(75.0%, 93.3%, 88.1%, 81.8% and 90.3%) were relatively high.CONCLUSION: HRME has a relatively high diagnostic value in the pathological classification of colon polyps. Thus, it may be an alternative to confocal microendoscopy in lower-resource or community-based settings.