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.

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.

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.

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.

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.

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.

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.

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.

Importance of the surrounding colonic mucosa in distinguishing between hyperplastic and adenomatous polyps during acetic acid chromoendoscopy

AIM: To examine the characteristics of colonic polyps, where it is difficult to distinguish adenomatous polyps from hyperplastic polyps, with the aid of acetic acid chromoendoscopy. METHODS: Acetic acid spray was applied to colonic polyps smaller than 10 mm before complete excision. Endoscopic images were taken before and 15-30 s after the acetic acid spray. Both pre-and post-sprayed images were shown to 16 examiners, who were asked to interpret the lesions as either hyperplastic or adenomatous polyps. Regression analysis was performed to determine which factors were most likely related to diagnostic accuracy. RESULTS: In 50 cases tested by the 16 examiners, the overall accuracy was 62.4% (499/800). Regression analysis demonstrated that surrounding colonic mucosa was the only factor that was significantly related to accuracy in discriminating adenomatous from hyperplastic polyps (P < 0.001). Accuracy was higher for polyps with linear surrounding colonic mucosa than for those with nodular surrounding colonic mucosa (P < 0.001), but was not related to the shape, location, or size of the polyp. CONCLUSION: The accuracy of predicting histology is significantly related to the pattern of colonic mucosa surrounding the polyp. Making a histological diagnosis of colon polyps merely by acetic acid spray is helpful for colon polyps with linear, regularly patterned surrounding colonic mucosa, and less so for those with nodular, irregularly patterned surrounding colonic mucosa.

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.

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.

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.

Endoscopic submucosal dissection vs endoscopic mucosal resection for colorectal polyps:A meta-analysis and metaregression with single arm analysis

BACKGROUND Endoscopic submucosal dissection(ESD)has shown to be effective in management of colorectal neoplasm in the Asian countries,while its implementation in Western countries where endoscopic mucosal resection(EMR)is preferred is still debatable.AIM To compare the surgical,histological,and oncological outcomes between ESD and EMR in the treatment of colorectal polyps,with subgroup analysis comparing the efficacy of ESD and EMR between Japan and the rest of the world.METHODS Embase and Medline databases were searched from inception to October 2020 in accordance with PRISMA guidelines for studies comparing en bloc,complete resection,margin involvement,resection time,need for additional surgery,complications,and recurrence rate of ESD with EMR.RESULTS Of 281344 colorectal polyps from 21 studies were included.When compared to EMR,the pooled analysis revealed ESD was associated with higher en bloc and complete resection rate,and lower lateral margin involvement and recurrence.ESD led to increased procedural time,need for additional surgery,and perforation risk.No significant difference in bleeding risk was found between the two groups.Meta-regression analysis suggested only right colonic polyps correlated with an increased perforation risk in ESD.Confounders including polyp size and invasion depth did not significantly influence the en bloc and complete resection rate,bleeding risk and recurrence.In subgroup analysis,Japan performed better than the rest of the world in both ESD and EMR with perforation risk of 4%and 0.0002%,respectively,as compared to perforation risk of 8%and 1%,respectively,in reports coming from rest of the world.CONCLUSION ESD resulted in better resection outcomes and lower recurrence compared to EMR.With appropriate training,ESD is preferred over EMR as the first-line therapy for resection of colorectal polyps,without restricting to lesions greater than 20 mm and those with high suspicion of submucosal invasion.

Quest for the best endoscopic imaging modality for computer-assisted colonic polyp staging

BACKGROUND It was shown in previous studies that high definition endoscopy, high magnification endoscopy and image enhancement technologies, such as chromoendoscopy and digital chromoendoscopy [narrow-band imaging(NBI), iScan] facilitate the detection and classification of colonic polyps during endoscopic sessions. However, there are no comprehensive studies so far that analyze which endoscopic imaging modalities facilitate the automated classification of colonic polyps. In this work, we investigate the impact of endoscopic imaging modalities on the results of computer-assisted diagnosis systems for colonic polyp staging.AIM To assess which endoscopic imaging modalities are best suited for the computerassisted staging of colonic polyps.METHODS In our experiments, we apply twelve state-of-the-art feature extraction methods for the classification of colonic polyps to five endoscopic image databases of colonic lesions. For this purpose, we employ a specifically designed experimental setup to avoid biases in the outcomes caused by differing numbers of images per image database. The image databases were obtained using different imaging modalities. Two databases were obtained by high-definition endoscopy in combination with i-Scan technology(one with chromoendoscopy and one without chromoendoscopy). Three databases were obtained by highmagnification endoscopy(two databases using narrow band imaging and one using chromoendoscopy). The lesions are categorized into non-neoplastic and neoplastic according to the histological diagnosis.RESULTS Generally, it is feature-dependent which imaging modalities achieve high results and which do not. For the high-definition image databases, we achieved overall classification rates of up to 79.2% with chromoendoscopy and 88.9% without chromoendoscopy. In the case of the database obtained by high-magnification chromoendoscopy, the classification rates were up to 81.4%. For the combination of high-magnification endoscopy with NBI, results of up to 97.4% for one database and up to 84% for the other were achieved. Non-neoplastic lesions were classified more accurately in general than non-neoplastic lesions. It was shown that the image recording conditions highly affect the performance of automated diagnosis systems and partly contribute to a stronger effect on the staging results than the used imaging modality.CONCLUSION Chromoendoscopy has a negative impact on the results of the methods. NBI is better suited than chromoendoscopy. High-definition and high-magnification endoscopy are equally suited.

Colo-colonic intussusception with post-polypectomy electrocoagulation syndrome:A case report

BACKGROUND Post-polypectomy electrocoagulation syndrome(PPES)can occur after colonoscopic polypectomy and is usually treated conservatively with a positive prognosis.Nevertheless,there can be cases with complications developing.CASE SUMMARY A 58-year-old woman,who had no previous medical history,visited the Emergency Department of another hospital with symptoms of abdominal pain and fever,1 d after multiple colonoscopic polypectomies.An abdominopelvic computed tomography(CT)scan demonstrated colo-colonic intussusception,and she was transferred to our hospital to consider an operation.CT showed colocolonic intussusception with PPES and no evidence of obstruction.The physical examination showed localized mild tenderness on the right sided abdomen.The patient fasted and was admitted for treatment with intravenous antibiotics(piperacillin/tazobactam 4.5 g each 8 h,ornidazole 500 mg each 12 h).After admission,the symptoms got better and a follow-up CT scan demonstrated resolution of the PPES and intussusception.The patient was discharged on hospital day 9.CONCLUSION Colo-colic intussusception can occur with PPES,and it can be properly treated conservatively.

Oxidative imbalance increases the risk for colonic polyp and colorectal cancer development

BACKGROUND The role of oxidative stress in the pathogenesis of colorectal carcinoma(CRC)has garnered considerable interest recently.Specific oxidative factors have been implicated in the pathogenesis of adenomatous polyps and ultimately adenocarcinoma.AIM To evaluate the effect of oxidative imbalance as quantified by specific serological markers in the development of sporadic colon adenocarcinoma.METHODS A total of 170 patients that underwent endoscopy of the lower gastrointestinal tract in a tertiary center within 3 years were included in the study.They were allocated in three groups;those with sporadic colon adenocarcinoma(n=56,32.9%),those with colonic polyps(n=33,19.4%)and healthy controls(n=81,47.7%).All patients were evaluated for oxidant activity and antioxidant capacity with serum measurements of specific markers such as vitamins A,25(OH)D3,E,C,B12,folic acid,glutathione,selenium(Se),zinc(Zn),free iron(Fe^(2+)),and malondialdehyde and results were compared between groups.RESULTS Serum levels of vitamins C,E,D,Se,Zn,vitamin B12 and total antioxidant capacity were significantly lower in the combined neoplasia/polyp group than in the control group(P=0.002,P=0.009,P<0.001,P<0.001,P<0.001,P=0.020 and P<0.001,correspondingly).Increased levels of vitamin E(P=0.004),vitamin D(P<0.001),Se(P<0.001)and Zn(P<0.001)seem to bestow a protective effect on the development of CRC.For vitamin D(P<0.001)and Zn(P=0.036),this effect seems to extend to the development of colon polyps as well.On the other hand,elevated serum levels of malondialdehyde are associated with a higher risk of CRC(OR=2.09 compared to controls,P=0.004).Regarding colonic polyp development,increased concentrations of vitaminΑand Fe^(2+) are associated with a higher risk,whereas lower levels of malondialdehyde with a lower risk.CONCLUSION Increased oxidative stress may play an important role in the pathogenesis and progression of CRC.Antioxidants’presence may exert a protective effect in the very early stages of colon carcinogenesis.

Pleomorphic leiomyosarcoma of the maxilla with metastasis to the colon:A case report

BACKGROUND Pleomorphic leiomyosarcomas make up around 8.6%of all leiomyosarcomas.They behave aggressively and often have poor prognoses.They can affect the gastrointestinal tract and retroperitoneum.To date,pleomorphic leiomyosarcoma involving the mesocolon have been reported in nine patients.CASE SUMMARY The patient was a 44-year-old man with a history of pleomorphic leiomyosarcoma of the left maxilla with metastasis to the lung and liver.His most recent positron emission tomography-computed tomography(PET-CT)scan showed uptake in the ascending and transverse colons.A colonoscopy revealed a 5.0 cm×3.5 cm×3.0 cm pedunculated polyp in the ascending colon.The polyp was removed using hot snare polypectomy technique and retrieved with Rothnet.Histopathologic examination of the polyp showed a metastatic pleomorphic leiomyosarcoma.CONCLUSION Uptake(s)on PET-CT in a patient with pleomorphic leiomyosarcoma should raise suspicion for metastasis.