Risk factors and endoscopic treatment for anastomotic stricture after resection in patients with colorectal cancer. / Factores de riesgo y tratamiento endoscópico para estenosis de anastomosis posterior a resección en pacientes con cáncer colorrectal.

INTRODUCTION: Benign strictures are frequent complications following colorectal surgery, with an incidence of up to 20%. Endoscopic treatment is safe and effective but there is not enough evidence for establishing stricture management at that anatomic level. AIM: To determine the risk factors associated with the development of stricture in patients with colorectal cancer and describe endoscopic treatment in those patients. MATERIALS AND METHODS: A retrospective study was conducted on patients with colorectal cancer that underwent surgery and anastomosis, evaluated through colonoscopy, within the time frame of 2014 to 2019. RESULTS: Of the 213 patients included in the study, 18.3% presented with stricture that was associated with the type of surgery. Intersphincteric resection was a risk factor (OR = 18.81, 95% CI: 3.31-189.40, p < .001). A total of 69.2% patients with stricture had a stoma, identifying it as a risk factor for stricture (OR = 7.07, 95% CI: 3.10-16.57, p < .001). Mechanical anastomotic stapling was performed in 87.4% of the patients that did not present with stricture, identifying it as a protective factor (OR = 0.41, 95% CI: 0.16-1.1, p = .04). Endoscopic treatment was required in 69.2% of the patients and provided favorable results in 83.3%. Only 2.6% of the patients had recurrence. No complications were reported. CONCLUSION: Intersphincteric resection and the presence of a stoma were independent risk factors for stricture, and mechanical anastomosis was a protective factor against stricture development. Endoscopic treatment was safe and effective.

Predictors of self-expanding metallic stent dysfunction in malignant gastric outlet obstruction. / Predictores de disfunción del stent metálico autoexplandible en la obstrucción de salida gástrica maligna.

INTRODUCTION AND OBJECTIVES: Self-expanding metallic stents (SEMS) are the ideal treatment for malignant gastric outlet obstruction (MGOO) in patients with a short life expectancy, but stent dysfunction is frequent. The primary aim of our study was to identify the predictive factors of SEMS dysfunction in MGOO and the secondary aim was to determine the technical success, clinical success, and nutritional impact after SEMS placement. MATERIAL AND METHODS: A retrospective, longitudinal study was conducted at the gastrointestinal endoscopy department of the Instituto Nacional de Cancerología in Mexico City. Patients diagnosed with MGOO that underwent SEMS placement within the time frame of January 2015 to May 2018 were included. We utilized the gastric outlet obstruction scoring system (GOOSS) to determine clinical success and SEMS dysfunction. RESULTS: The study included 43 patients, technical success was 97.7% (n=42), and clinical success was 88.3% (n=38). SEMS dysfunction presented in 30.2% (n=13) of the patients, occurring in<6 months after placement in 53.8% (n=7) of them. In the univariate analysis, the histologic subtype, diffuse gastric adenocarcinoma (p=0.02) and the use of uncovered SEMS (p=0.02) were the variables associated with dysfunction. Albumin levels and body mass index did not increase after SEMS placement. Medical follow-up was a mean 5.8 months (1-24 months). CONCLUSIONS: SEMS demonstrated adequate technical and clinical efficacy in the treatment of MGOO. SEMS dysfunction was frequent and diffuse type gastric cancer and uncovered SEMS appeared to be dysfunction predictors.

The Mexican consensus on the diagnosis, treatment, and prevention of NSAID-induced gastropathy and enteropathy. / Consenso mexicano sobre diagnóstico, prevención y tratamiento de la gastropatía y enteropatía por antiinflamatorios no esteroideos.

More than 30 million persons worldwide take nonsteroidal anti-inflammatory drugs (NSAIDs) on a daily basis, and annual consumption is increasing. In addition to their analgesic and anti-inflammatory properties, NSAIDs also produce well-known gastrointestinal adverse events. There is no consensus in Mexico on the diagnosis, treatment, and prevention of NSAID-induced gastropathy and enteropathy, and so the Asociación Mexicana de Gastroenterología brought together a group of experts to establish useful recommendations for the medical community. Thirty-three recommendations were formulated in the present consensus, highlighting the fact that the risk for NSAID-induced gastrointestinal toxicity varies according to the drug employed and its pharmacokinetics, which should be taken into account at the time of prescription. The risk factors for gastroduodenal complications due to NSAIDs are: a history of peptic ulcer, age above 65 years, high doses of NSAIDs, Helicobacter pylori infection, and the presence of severe comorbidities. The symptoms and gastroduodenal damage induced by NSAIDs vary, ranging from an asymptomatic course to the presentation of iron-deficiency anemia, bleeding, stricture, and perforation. Capsule endoscopy and enteroscopy are direct diagnostic methods in NSAID enteropathy. Regarding prevention, the minimum dose of an NSAID needed to achieve the desired effect, administered for the shortest period of time, is the recommendation. Finally, proton pump inhibitors are the gold standard for the prophylaxis and treatment of gastroduodenal effects, but they are not useful in enteropathy.

The Mexican consensus on the detection and treatment of early gastric cancer. / Consenso mexicano sobre detección y tratamiento del cáncer gástrico incipiente.

Gastric cancer is one of the most frequent neoplasias in the digestive tract and is the result of premalignant lesion progression in the majority of cases. Opportune detection of those lesions is relevant, given that timely treatment offers the possibility of cure. There is no consensus in Mexico on the early detection of gastric cancer, and therefore, the Asociación Mexicana de Gastroenterología brought together a group of experts and produced the "Mexican consensus on the detection and treatment of early gastric cancer" to establish useful recommendations for the medical community. The Delphi methodology was employed, and 38 recommendations related to early gastric cancer were formulated. The consensus defines early gastric cancer as that which at diagnosis is limited to the mucosa and submucosa, irrespective of lymph node metástasis. In Mexico, as in other parts of the world, factors associated with early gastric cancer include Helicobacter pylori infection, a family history of the disease, smoking, and diet. Chromoendoscopy, magnification endoscopy, and equipment-based image-enhanced endoscopy are recommended for making the diagnosis, and accurate histopathologic diagnosis is invaluable for making therapeutic decisions. The endoscopic treatment of early gastric cancer, whether dissection or resection of the mucosa, should be preferred to surgical management, when similar oncologic cure results can be obtained. Endoscopic surveillance should be individualized.

Mantle cell lymphoma with involvement of the digestive tract. / Linfoma del manto con afección del tubo digestivo.

INTRODUCTION AND AIM: Mantle cell lymphoma is an aggressive subtype of B-cell non-Hodgkin lymphoma and its incidence is 0.5/100,000 inhabitants. Gastrointestinal involvement at diagnosis is 15-30%. The aim of our study was to analyze the clinical and endoscopic characteristics of mantle cell lymphoma affecting the digestive tract. MATERIAL AND METHODS: A retrospective study was conducted, based on a case series of patients with mantle cell lymphoma affecting the gastrointestinal tract that were diagnosed over a 10-year period. RESULTS: Ten patients (11.7%) had gastrointestinal tract involvement. The upper endoscopic findings were polypoid lesions (66%), thickened folds (44%), and nonspecific changes in the mucosa (33%). At colonoscopy, polypoid lesions were viewed in 100% of the patients and ulcerated lesions in 40%. CONCLUSION: Polypoid lesions are the most common endoscopic characteristics in patients with mantle cell lymphoma of the gastrointestinal tract. Upper endoscopy and colonoscopy should be carried out on patients with mantle cell lymphoma, even those with nonspecific symptoms, to check their gastrointestinal status. Gastrointestinal involvement has an impact on disease staging.

The fourth Mexican consensus on Helicobacter pylori. / IV consenso mexicano sobre Helicobacter pylori.

Important advances have been made since the last Mexican consensus on the diagnosis and treatment of Helicobacter pylori (H. pylori) infection was published in 2007. Therefore, the Asociación Mexicana de Gastroenterología summoned 20 experts to produce "The Fourth Mexican Consensus on Helicobacter pylori". From February to June 2017, 4 working groups were organized, a literature review was performed, and 3 voting rounds were carried out, resulting in the formulation of 32 statements for discussion and consensus. From the ensuing recommendations, it was striking that Mexico is a country with an intermediate-to-low risk for gastric cancer, despite having a high prevalence of H. pylori infection. It was also corroborated that peptic ulcer disease, premalignant lesions, and histories of gastric cancer and mucosa-associated lymphoid tissue lymphoma should be considered clear indications for eradication. The relation of H. pylori to dyspeptic symptoms continues to be controversial. Eradication triple therapy with amoxicillin, clarithromycin, and a proton pump inhibitor should no longer be considered first-line treatment, with the following 2 options proposed to take its place: quadruple therapy with bismuth (proton pump inhibitor, bismuth subcitrate, tetracycline, and metronidazole) and quadruple therapy without bismuth (proton pump inhibitor, amoxicillin, clarithromycin, and metronidazole). The need for antimicrobial sensitivity testing when 2 eradication treatments have failed was also established. Finally, the promotion of educational campaigns on the diagnosis and treatment of H. pylori for both primary care physicians and the general population were proposed.

Fully covered stents versus partially covered stents for palliative treatment of esophageal cancer: Is there a difference? / Prótesis totalmente cubiertas versus parcialmente cubiertas para el tratamiento paliativo del cáncer de esófago: ¿hay alguna diferencia?

INTRODUCTION AND AIMS: Malignant dysphagia is difficulty swallowing resulting from esophageal obstruction due to cancer. The goal of palliative treatment is to reduce the dysphagia and improve oral dietary intake. Self-expandable metallic stents are the current treatment of choice, given that they enable the immediate restoration of oral intake. The aim of the present study was to describe the results of using totally covered and partially covered esophageal stents for palliating esophageal cancer. MATERIALS AND METHODS: A retrospective study was conducted on patients with inoperable esophageal cancer treated with self-expandable metallic stents. The 2 groups formed were: group A, which consisted of patients with a fully covered self-expandable stent (SX-ELLA®), and group B, which was made up of patients with a partially covered self-expandable stent (Ultraflex®). RESULTS: Of the 69-patient total, 50 were included in the study. Group A had 19 men and 2 women and their mean age was 63.6 years (range 41-84). Technical success was achieved in 100% (n=21) of the cases and clinical success in 90.4% (n=19). Group B had 24 men and 5 women and their mean age was 67.5 years (range 43-92). Technical success was achieved in 100% (n=29) of the cases and clinical success in 89.6% (n=26). Complications were similar in both groups (33.3 vs. 51.7%). CONCLUSION: There was no difference between the 2 types of stent for the palliative treatment of esophageal cancer with respect to technical success, clinical success, or complications.

Mexican consensus on dyspepsia. / Consenso mexicano sobre la dispepsia.

Since the publication of the 2007 dyspepsia guidelines of the Asociación Mexicana de Gastroenterología, there have been significant advances in the knowledge of this disease. A systematic search of the literature in PubMed (01/2007 to 06/2016) was carried out to review and update the 2007 guidelines and to provide new evidence-based recommendations. All high-quality articles in Spanish and English were included. Statements were formulated and voted upon using the Delphi method. The level of evidence and strength of recommendation of each statement were established according to the GRADE system. Thirty-one statements were formulated, voted upon, and graded. New definition, classification, epidemiology, and pathophysiology data were provided and include the following information: Endoscopy should be carried out in cases of uninvestigated dyspepsia when there are alarm symptoms or no response to treatment. Gastric and duodenal biopsies can confirm Helicobacter pylori infection and rule out celiac disease, respectively. Establishing a strong doctor-patient relationship, as well as dietary and lifestyle changes, are useful initial measures. H2-blockers, proton-pump inhibitors, prokinetics, and antidepressants are effective pharmacologic therapies. H.pylori eradication may be effective in a subgroup of patients. There is no evidence that complementary and alternative therapies are beneficial, with the exception of Iberogast and rikkunshito, nor is there evidence on the usefulness of prebiotics, probiotics, or psychologic therapies. The new consensus statements on dyspepsia provide guidelines based on up-to-date evidence. A discussion, level of evidence, and strength of recommendation are presented for each statement.

Microbiota studies in the bile duct strongly suggest a role for Helicobacter pylori in extrahepatic cholangiocarcinoma.

Biliary tract cancer or extrahepatic cholangiocarcinoma (ECCA) represents the sixth commonest cause of cancer in the gastrointestinal tract in western countries. We aimed to characterize the microbiota and its predicted associated functions in the biliary tract of ECCA and benign biliary pathology (BBP). Samples were taken from 100 patients with ECCA and 100 patients with BBP by endoscopic cholangio-pancreatography for DNA extraction. Ten patients with ECCA and ten with BBP were selected for microbiota studies using the V4-16S rRNA gene and sequenced in Illumina platform. Microbiota analyses included sample-to-sample distance metrics, ordination/clustering and prediction of functions. Presence of Nesterenkonia sp. and Helicobacter pylori cagA and vacA genes were tested in the 100 ECCA and 100 BBP samples. Phylum Proteobacteria dominated all samples (60.4% average). Ordination multicomponent analyses showed significant microbiota separation between ECCA and BBP (p 0.010). Analyses of 4002 operational taxonomic units with presence variation in at least one category probed a separation of ECCA from BBP. Among these, Nesterenkonia decreased, whereas Methylophilaceae, Fusobacterium, Prevotella, Actinomyces, Novosphingobium and H. pylori increased in ECCA. Predicted associated functions showed increased abundance of H. pylori virulence genes in ECCA. cagA and vacA genes were confirmed by PCR in ECCA and BBP samples. This is the first microbiota report in ECCA and BBP to show significant changes in microbial composition. Bacterial species unusual for human flora were found: Methylophilaceae and Nesterenkonia are reported in hypersaline soils, and Mesorhizobium is a nitrogen-fixing bacterium. Enrichment of virulence genes confirms previous studies suggesting that H. pylori might be associated with ECCA.

[The Mexican consensus on gastroesophageal reflux disease. Part II]. / Consenso mexicano de enfermedad por relujo gastroesofágico. Parte II.

OBJECTIVE: To update the themes of endoscopic and surgical treatment of Gastroesophageal Reflux Disease (GERD) from the Mexican Consensus published in 2002. METHODS: Part I of the 2011 Consensus dealt with the general concepts, diagnosis, and medical treatment of this disease. Part II covers the topics of the endoscopic and surgical treatment of GERD. In this second part, an expert in endoscopy and an expert in GERD surgery, along with the three general coordinators of the consensus, carried out an extensive bibliographic review using the Embase, Cochrane, and Medline databases. Statements referring to the main aspects of endoscopic and surgical treatment of this disease were elaborated and submitted to specialists for their consideration and vote, utilizing the modified Delphi method. The statements were accepted into the consensus if the level of agreement was 67% or higher. RESULTS: Twenty-five statements corresponding to the endoscopic and surgical treatment of GERD resulted from the voting process, and they are presented herein as Part II of the consensus. The majority of the statements had an average level of agreement approaching 90%. CONCLUSION: Currently, endoscopic treatment of GERD should not be regarded as an option, given that the clinical results at 3 and 5 years have not demonstrated durability or sustained symptom remission. The surgical indications for GERD are well established; only those patients meeting the full criteria should be candidates and their surgery should be performed by experts.

[Mexican consensus on portal hypertension]. / Consenso Mexicano de Hipertensión Portal.

The aim of the Mexican Consensus on Portal Hypertension was to develop documented guidelines to facilitate clinical practice when dealing with key events of the patient presenting with portal hypertension and variceal bleeding. The panel of experts was made up of Mexican gastroenterologists, hepatologists, and endoscopists, all distinguished professionals. The document analyzes themes of interest in the following modules: preprimary and primary prophylaxis, acute variceal hemorrhage, and secondary prophylaxis. The management of variceal bleeding has improved considerably in recent years. Current information indicates that the general management of the cirrhotic patient presenting with variceal bleeding should be carried out by a multidisciplinary team, with such an approach playing a major role in the final outcome. The combination of drug and endoscopic therapies is recommended for initial management; vasoactive drugs should be started as soon as variceal bleeding is suspected and maintained for 5 days. After the patient is stabilized, urgent diagnostic endoscopy should be carried out by a qualified endoscopist, who then performs the corresponding endoscopic variceal treatment. Antibiotic prophylaxis should be regarded as an integral part of treatment, started upon hospital admittance and continued for 5 days. If there is treatment failure, rescue therapies should be carried out immediately, taking into account that interventional radiology therapies are very effective in controlling refractory variceal bleeding. These guidelines have been developed for the purpose of achieving greater clinical efficacy and are based on the best evidence of portal hypertension that is presently available.

Immunological fecal occult blood test vs. serum ferritin for detection of colorectal neoplasia in high risk asymptomatic population.

INTRODUCTION: Fecal occult blood tests (FOBT) (biochemical or immunological) are based on the fact that most of the polyps or cancers bleed. Anemia due to iron deficiency is a wellknown sign for colorectal cancer (CRC). Ferritin is frequently used to select candidates for colonoscopy. OBJECTIVE: To determine and compare the diagnostic value of immunological fecal occult blood test vs. ferritin for the detection of colorectal neoplasia (cancer or polyps) in high-risk patients. METHODS: A transversal prospective study at National Cancer Institute, Mexico City, in consecutive asymptomatic subjects at high risk for CRC was performed, comparing two tests (immunological against serum ferritin) with colonoscopy plus histopathology. Both tests were performed in a blindly fashion previous to colonoscopy. RESULTS: Fifty patients were included in the study; twenty-eight patients had colorectal neoplasia (21 CRC, 7 adenomas). All immunologic tests for fecaloccult blood were positive in patients with colorectal lesions (sensitivity, 98%). There was no difference between the mean ferritin levels in patients with CRC or adenomas vs. those with negative colonoscopy (p = 0.58). The cutoff point where significant relationship between serum ferritin levels and colon lesions was established was ?46 ng/mL. In anemic patients with serum ferritin levels <46 ng/mL, the test had a sensitivity 53%, specificity 86%, positive predictive value 83%, and negative predictive value of 59% (p = 0.003). CONCLUSIONS: The immunological FOBT is a better diagnostic tool than serum ferritin for screening of colonic neoplasms.

[IT-Knife-2 electroincision as primary treatment of anastomotic strictures]. / Electroincisión con IT-Knife-2 como tratamiento primario de las estenosis posquirúrgicas.

BACKGROUND: Dysphagia is a common problem after surgical stenosis (5% to 55%) and can be refractory to conventional endoscopic treatment in 22% of cases. It has been proposed that electro-incision is an alternative and effective treatment. OBJECTIVE: To evaluate the effectiveness of electro-incision with the insulation-tipped diathermic Knife-2 (IT-Knife-2) in the treatment of dysphagia produced by surgical anastomotic strictures. METHODS: Longitudinal and case-series study from August 2009 to June 2010. Eight consecutive patients with anastomotic stricture-associated dysphagia and naive to endoscopic treatment were included. We performed three or more radiated cuts in the stricture until passage of the gastroscope was achieved with IT-Knife-2 and electrocautery (ERBE IC 200) with a 70-100 W energy cut-off and 25 W coagulation. We carried out measurements at baseline and 15 days after the intervention, evaluating the dysphagia by the Atkinson grading scale and endoscopic changes. RESULTS: The majority of patients were at clinical stage IV with an Eastern Cooperative Oncology Group score of 1 - 3 and Karnofsky between 40 and 90. At the time of endoscopic diagnosis, patients had dysphagia grade II and III. Strictures in all of the cases were short in length and had a diameter of minor than 5 mm. At 15 days of the intervention, no patient demonstrated dysphagia (p = 0.0013) and the anastomotic diameters was more than 9.5 mm and without evidence of stenosis (p = 0.0001). None of our patients presented postincisional complications. CONCLUSIONS: Electro-incision with IT-Knife-2 is effective as primary treatment for the relief of benign dysphagia associated with postsurgical anastomotic stenosis."

[The value of targeted biopsies with endoscopic magnification and narrow band image vs. chromoendoscopy for the diagnosis of gastric metaplasia]. / Valor de la biopsia dirigida con magnificación endoscópica más imagen de banda estrecha vs. Cromoendoscopia para el diagnóstico de metaplasia gástrica.

INTRODUCTION: Endoscopy is the better test to detect premalignant lesions, but its main problem is the sampling error. OBJECTIVES: To evaluate the diagnostic usefulness of endoscopic biopsies using narrow band imaging (NBI) vs. chromoendoscopy for diagnosing gastric intestinal metaplasia. METHODS: Forty one patients were studied with conventional endoscopy, NBI magnification endoscopy and chromoendoscopy (3% acetic acid, 0.6% indigo carmine) for examination of gastric antrum. Biopsies were taken randomly from the antrum, body and incisura angularis. Additional biopsies were taken from areas with villous or crypt pattern according to NBI and chromoendoscopy examination (targeted biopsies). RESULTS: 240 biopsies were taken, 205 randomized biopsies and 35 targeted biopsies. Intestinal metaplasia was found in 25 randomized biopsies and 9 directed samples (12% vs. 25.7%). The NBI and chromoendoscopy had sensitivity of 70% vs. 77%, specificity of 97% vs. 98%, with diagnostic accuracy of 96% vs. 97%, respectively. Random biopsies and targeted biopsies had a sensitivity of 91% vs. 74%, specificity of 51% vs. 95%, and diagnostic accuracy of 93% vs. 86%, respectively. The intra-observer variability showed a k value of 0.86 (range 0.74 to 0.99). CONCLUSION: Targeted biopsies are more specific than random biopsies to detect gastric intestinal metaplasia. NBI and chromoendoscopy may be used similarly to guide biopsies.

[Endoscopic inanimate biological simulators for training in endoscopic mucosal dissection]. / Entrenamiento en la disección endoscópica de la submucosa "mediante el uso de simuladores biológicos inanimados.

BACKGROUND: Simulators have been used as a training method; they allow training, skill development, standardization of techniques and the performance of a greater number of risk-free procedures. Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric cancer since it allows en bloc resection of larger lesions however requires longer procedure time and has more complications than endoscopic mucosal resection. OBJECTIVE: To evaluate the use of biological inanimate simulators in endoscopic training for the development of skills required for ESD. METHODS: Experimental design using a biological inanimate simulator to evaluate the development of endoscopic skills. Five trained endoscopists with knowledge of the ESD technique, but without previous experience were selected. Technical success, complication rate and procedure time were evaluated. Each participant performed a self-evaluation. RESULTS: 18 lesions of 10-20 mm in diameter were dissected, with a mean area of 2.64 ± 2 cm2 and a mean procedure time of 21.08 ± 14.01 minutes (5.48 - 48.61). Self-evaluation and instructor's evaluation showed a strong positive correlation. There was no correlation between lesion size and procedure time. There was one perforation (5.8%), which was successfully managed with one endoclip. Complications such as bleeding could not be assed. CONCLUSIONS: The use of inanimate biological simulators allows training in complex endoscopic procedures such as ESD with a wide safety margin. Lesion size did not correlate with procedure time. It is necessary to increase the number of procedures to improve the learning curve. This simulator does not allow evaluation of complications other than perforations.

Dilated intercellular spaces in subtypes of gastroesophagic reflux disease.

BACKGROUND: Dilatation of the intercellular spaces by electron microscopy has been considered as an early morphological marker of tissue injury in gastroesophageal reflux disease. The degree of dilatation in Barret's esophagus in currently unknown. OBJECTIVES: To determine the frequency of dilated intervellular spaces in Barrett's esophagus. MATERIAL AND METHODS: Cross-sectional and prospective analysis of consecutive patients with gastroesophageal reflux disease. We selected symptomatic patients > 18 years and both sexes. Patients with recent PPI use (< 14 days), H-2 antagonists, NSAID's or previous upper GI tract surgery were excluded. VARIABLES INCLUDED: Clinical-demographic data, Carlsson-Dent score, conventional endoscopy findings, pH-metry results (in non-erosive) and normal mucosal biopsies at 2 and 5 cm above the squamocolumnar junction. Dilation of intercellular spaces was measured by electron microscopy. STATISTICS: Chi square test with a significance level 0.05 was calculated. The following four groups were compared: a) non-erosive reflux disease (n = 14); b) erosive esophagitis (n = 5); c) Barrett's esophagus (n = 13); and d) healthy controls (n = 5). RESULTS: the dilation of intervellular spaces was increasingly greater form non-erosive revlux to Barrett's esophagus and higher in biopsies taken at 5 cm than at 2 cm of the squamous columnar junction (2.72 +/- 1.35 vs. 1.71 +/- 0.48 microg) (p = 0.001). There was no difference between biopsies at 2 and 5 cm in the order groups. CONCLUSION: dilation of intercellular spaces was greater in Barrett s esophagus than in the other groups and higher at 5 cm from the squamocolumnar junction.