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BACKGROUND Low-volume preparations for colonoscopy have shown similar efficacy compared to high-volume ones in randomized controlled trials (RCT). However, most RCTs do not provide data about clinical outcomes including lesions detection rate. Moreover, real-life comparisons are lacking. AIM To compare efficacy (both in terms of adequate bowel preparation and detection of colorectal lesions) and tolerability of a high-volume (HV: 4 L polyethylene glycol, PEG) and a low-volume (LV: 2 L PEG plus bisacodyl) bowel preparation in a real-life setting. METHODS Consecutive outpatients referred for colonoscopy were prospectively enrolled between 1 December 2014 and 31 December 2016. Patients could choose either LV or HV preparation, with a day-before schedule for morning colonoscopies and a split-dose for afternoon procedures. Adequate bowel preparation according to Boston Bowel Preparation Scale (BBPS), clinical outcomes including polyp detection rate (PDR), adenoma detection rate (ADR), advanced adenoma detection rate (AADR), sessile/serrated lesion detection rate (SDR) and cancer detection rate and self-reported tolerability of HV and LV were blindly assessed. RESULTS Total 2040 patients were enrolled and 1815 (mean age 60.6 years, 50.2% men) finally included. LV was chosen by 52% of patients (50.8% of men, 54.9% of women). Split-dose schedule was more common with HV (44.7% vs 38.2%, P = 0.005). High-definition scopes were used in 33.4% of patients, without difference in the two groups (P = 0.605). HV and LV preparations showed similar adequate bowel preparation rates (89.2% vs 86.6%, P = 0.098), also considering the two different schedules (HV split-dose 93.8% vs LV split-dose 93.6%, P = 1; HV day-before 85.5% vs LV day-before 82.3%, P = 0.182). Mean global BBPS score was higher for HV preparations (7.1 ± 1.7 vs 6.8 ± 1.6, P < 0.001). After adjustment for sex, age and indications for colonoscopy, HV preparation resulted higher in PDR [Odds ratio (OR) 1.32, 95%CI: 1.07-1.63, P = 0.011] and ADR (OR 1.29, 95%CI 1.02–1.63, P = 0.038) and comparable to LV in AADR (OR 1.51, 95%CI 0.97-2.35, P = 0.069), SDR and cancer detection rate. The use of standard-definition colonoscopes was associated to lower PDR (adjusted OR 1.59, 95%CI: 1.22-2.08, P < 0.001), ADR (adjusted OR 1.71, 95%CI: 1.26–2.30, P < 0.001) and AADR (adjusted OR 1.97, 95%CI: 1.09-3.56, P = 0.025) in patients receiving LV preparation. Mean Visual Analogue Scale tolerability scored equally (7, P = 0.627) but a ≥ 75% dose intake was more frequent with LV (94.6% vs 92.1%, P = 0.003). CONCLUSION In a real-life setting, PEG-based low-volume preparation with bisacodyl showed similar efficacy and tolerability compared to standard HV preparation. However, with higher PDR and ADR, HV should still be considered as the reference standard for clinical trials and the preferred option in screening colonoscopy, especially when colonoscopy is performed with standard resolution imaging.

ObjectiveLow adenoma detection rates (ADR) are linked to increased postcolonoscopy colorectal cancer rates and reduced cancer survival. Devices to enhance mucosal visualisation such as Endocuff Vision (EV) may improve ADR. This multicentre randomised controlled trial compared ADR between EV-assisted colonoscopy (EAC) and standard colonoscopy (SC).DesignPatients referred because of symptoms, surveillance or following a positive faecal occult blood test (FOBt) as part of the Bowel Cancer Screening Programme were recruited from seven hospitals. ADR, mean adenomas per procedure, size and location of adenomas, sessile serrated polyps, EV removal rate, caecal intubation rate, procedural time, patient experience, effect of EV on workload and adverse events were measured.Results1772 patients (57% male, mean age 62 years) were recruited over 16 months with 45% recruited through screening. EAC increased ADR globally from 36.2% to 40.9% (P=0.02). The increase was driven by a 10.8% increase in FOBt-positive screening patients (50.9% SC vs 61.7% EAC, PConclusionEV significantly improved ADR in bowel cancer screening patients and should be used to improve colonoscopic detection.Trial registration numberNCT02552017, Results; ISRCTN11821044, Results.

The freeze on endoscopy activity during the first wave of the COVID-19 pandemic was followed by radical pathway redesign to minimise risks of viral transmission. However, most endoscopy lists are running at reduced capacity due to the need for extra safety measures, staff absences and there is a concern about a post-COVID surge in demand as symptomatic patients emerge from isolation. ‘Desperate times call for desperate measures’: to mitigate pressures on endoscopy services the British Society of Gastroenterology Endoscopy committee set up a COVID-19 Research Group to consider potential roles for novel alternative diagnostic technologies and National Health Service (NHS) England has provided £6 million to deliver colon capsule endoscopy services over the next year. Could this terrible pandemic be the impetus needed for capsule endoscopy to replace conventional endoscopy as the primary diagnostic tool? ‘In the midst of every crisis lies great opportunity.’ Most clinicians remain hesitant about embracing capsule endoscopy of the colon or upper gastrointestinal (GI) tract, although small bowel examination is widely accepted. Colonoscopy is performed in 1.5% of the population per annum, demand is increasing, it is undignified and uncomfortable and often necessitates the use of sedatives and analgesia. About 90% of procedures reveal no clear cause for symptoms although incidental polyps are found in 20%.1 It is hoped that biomarker assays such as the faecal immunochemical test (FIT) for haemoglobin and calprotectin may help select appropriate patients who need colonoscopy for biopsy or polypectomy. However, in setting FIT and calprotectin referral thresholds there is a trade-off between reducing referral rate and increasing pathology miss rate which puts patients and clinicians in a dilemma. Not all …

Myeloid derived suppressor cells (MDSC) are a heterogeneous population of immature myeloid cells that accumulate in circulation of cancer patients and at tumor sites where they suppress anti-tumor immunity. We previously reported that in a colon cancer prevention trial of a MUC1 vaccine tested in individuals at increased risk for colon cancer, those who did not mount immune response to the vaccine had higher pre-vaccination levels of circulating MDSC compared to those who did. We also reported that individuals with pancreatic premalignancy, Intraductal Papillary Mucinous Neoplasm (IPMN), had increased circulating levels of MDSC that inversely correlated with spontaneous antibody responses against the pancreatic tumor associated antigen MUC1, abnormally expressed on IPMN. Accumulation of MDSC in cancer and their immunosuppressive role had been well established but their presence in premalignancy was unexpected. In this study we compared MDSC in premalignancy with those in cancer with the hypothesis that there might be differences in the composition of various MDSC subpopulations and their immunosuppressive functions due to different lengths of exposure to disease and/or different tissue microenvironments. In cohorts of patients with premalignant polyps, colon cancer, premalignant IPMN, and pancreatic cancer, we confirmed higher levels of MDSC in premalignancy compared to healthy controls, higher levels of MDSC in cancer compared to premalignancy, but no difference in their subpopulation composition or immunosuppressive capacity. We show that levels of MDSC in premalignancy correlate negatively in vivo with spontaneous MUC1-specific antibody responses and in vitro with polyclonal T cell proliferation and IFN-γ secretion.

Aims: Colectomy is the current approach for patients with endoscopically unresectable benign polyps but risks considerable morbidity. Full-thickness laparoendoscopic excision (FLEX) is a novel procedure, specifically developed to treat endoscopically unresectable benign colonic polyps, which could reduce the treatment burden of the current approach and improve outcomes. However, traditional evaluations of surgical innovations lack methodological rigour. This study reports the development and feasibility of the FLEX procedure in selected patients. Method: A prospective development study using the Idea, Development, Evaluation, Assessment, Long-term study (IDEAL) framework was undertaken, by one surgeon, of the FLEX procedure in selected patients with endoscopically unresectable benign colonic polyps. Three-dimensional (3D)-CT colonography reconstructions were used preoperatively to rehearse patient-specific, critical manoeuvres. Targetted, full-thickness excision was performed: after marking the margin of the caecal polyp using circumferential endoscopic argon plasma coagulation, transmural endoscopic sutures were used to evert the bowel and resection was undertaken by laparoscopic linear stapling. Feasibility outcomes (establishing ‘local success’) included evidence of complete polyp resection without adverse events (especially safe closure of the excision site). Results: Ten patients [median (interquartile range) age: 74 (59-78) years] with polyp median diameters of 35 (30–41) mm, were referred for and consented to receive the FLEX procedure. During the same time frame, no patient underwent colectomy for benign polyps. One further patient received FLEX for local excision of a presumed malignant polyp because severe comorbidity prohibited standard procedures. The FLEX procedure was successfully performed locally, with complete resection of the polyp and safe closure of the excision site, in eight patients. Three noncompleted procedures were converted to laparoscopic segmental colectomy under the same anaesthetic because of endoscopic inaccessibility (two patients) and transcolonic suture failure (one patient). Conclusions: The FLEX procedure is still under development. Early data demonstrate that it is safe for excision of selected benign polyps. Modifications to transcolonic suture delivery are now required and there is a need for wider adoption before more definitive evaluation can be performed.What does this paper add to the literature?This study has shown, through an examination of the feasibility of the FLEX procedure for resection of complex, benign colonic polyps in clinical practice, that incorporating the IDEAL framework guidance can enhance transparency and reduce information bias.

Background and aimColorectal cancer (CRC) has an increased impact on the Lebanese population’s morbidity and mortality. This study evaluated the situation of adenoma detection in an outpatient clinic in Lebanon.Patients and methods918 patients underwent colonoscopy over a period of 24 months by a qualified physician. Biopsy results were divided into normal versus abnormal colonic tissue, which was further subdivided into number of polyps and cancer.ResultsOut of 918 individuals included, 82 cases of Crohn’s colitis (8.93%) and 22 cases of ulcerative colitis (2.39%) were identified. A total of 42 cases of CRC (4.58%) and 188 cases of adenomatous polyps (20.48%) were identified. The data show that age >50 years and male gender significantly correlate with increased incidence of precancerous and cancerous polyps. Further exploring the results by age groups and gender, detection of adenomatous polyps in women aged 40–49 (8.33%) was significantly different from their female counterparts aged ≥50 years old (25.26%) (pConclusionWithin the limitations of this study, the incidence of CRC and adenomatous polyps falls in the high range compared with international studies. Furthermore, symptomatic male patients aged 40–49 appear to exhibit detection rates of adenomas similar to their counterparts aged ≥50 years old. Subjects younger than 50 years underwent diagnostic rather than screening colonoscopy, which introduces some selection bias. Nevertheless, these findings can serve as a basis for further studies.

With significant advances in the management of gastrointestinal disease there has been a move from diagnosing advanced pathology, to detecting early lesions that are potentially amenable to curative endoscopic treatment. This has required an improvement in diagnostics, with a focus on identifying and characterising subtle mucosal changes. There is great interest in the use of optical technologies to predict histology and enable the formulation of a real-time in vivo diagnosis, a so-called ‘optical biopsy’. The aim of this review is to explore the evidence for the use of the current commercially available imaging techniques in the gastrointestinal tract.

To the Editor We read with interest the recent data reported by IJspeert et al ,1 Biswas et al 2 and Moreira et al 3 whom evaluated the prevalence of serrated polyposis syndrome (SPS), a disease characterised by the development of multiple serrated polyps throughout the colon with an increased risk to develop colorectal cancer (CRC),4 inside CRC screening programmes. A guaiac faecal occult blood test cohort from the UK showed a frequency of SPS ranging from 0.03% to 0.66%.1 ,2 Other cohorts based on primary colonoscopy showed a prevalence of SPS between 0.1% and 0.4%.1 The only published data on SPS frequency within faecal immunochemical test (FIT) programmes are from Spain and ranged from 0.34% to 0.8%.1 ,3 Since FIT has widely become the method of choice for …

BackgroundColonoscopy is a commonly used modality for screening and surveillance of colorectal cancer (CRC). Therefore, it is essential to have adequate bowel preparation (prep) for the procedure which depends on type of bowel regimens, diet before colonoscopy and timing of the procedure.AimsThe purpose of this study is to analyse the effect of multiple factors on adenoma detection rate (ADR) and prep quality of colonoscopy. This is the also the first study determining outcomes based on various combinations of diet, timing of the procedure and bowel prep regimens.MethodsThis is a retrospective single-centre observational study. Data about diet before procedure, bowel prepprep regimen and timing of the procedure was collected for patients coming for screening colonoscopy.ResultsPatients with split prep had higher good prep rates (73.8% vs 56.2%) and higher ADRs (34.2 % vs 29.9%) as compared with non-split prep. The good prep quality (65.8% vs 62.1%) and ADRs (31.9% vs 31.5%) were comparable in patients who received clear liquid diet as compared with low residue diet. The good results of bowel prep were obtained with split prep with either clear liquids or low residue diet irrespective of the timing of procedure. The poor prep was noticed in patients who underwent procedure in afternoon, with a low restrictive diet and non-split bowel regimen.ConclusionsThe current study adds to our knowledge about the combined effect of multiple variables affecting the bowel prep quality and ADR. It is imperative to opt for the best combination required for colonoscopy, as this will influence the effectiveness of colonoscopies regarding timely cancer detection and prevention.

Background Most colon cancers start with dysregulated Wnt/β-catenin signalling and remain a major therapeutic challenge. Examining whether HAMLET (human α-lactalbumin made lethal to tumour cells) may be used for colon cancer treatment is logical, based on the properties of the complex and its biological context. Objective To investigate if HAMLET can be used for colon cancer treatment and prevention. Apc Min/+ mice, which carry mutations relevant to hereditary and sporadic human colorectal tumours, were used as a model for human disease. Method HAMLET was given perorally in therapeutic and prophylactic regimens. Tumour burden and animal survival of HAMLET-treated and sham-fed mice were compared. Tissue analysis focused on Wnt/β-catenin signalling, proliferation markers and gene expression, using microarrays, immunoblotting, immunohistochemistry and ELISA. Confocal microscopy, reporter assay, immunoprecipitation, immunoblotting, ion flux assays and holographic imaging were used to determine effects on colon cancer cells. Results Peroral HAMLET administration reduced tumour progression and mortality in Apc Min/+ mice. HAMLET accumulated specifically in tumour tissue, reduced β-catenin and related tumour markers. Gene expression analysis detected inhibition of Wnt signalling and a shift to a more differentiated phenotype. In colon cancer cells with APC mutations, HAMLET altered β-catenin integrity and localisation through an ion channel-dependent pathway, defining a new mechanism for controlling β-catenin signalling. Remarkably, supplying HAMLET to the drinking water from the time of weaning also significantly prevented tumour development. Conclusions These data identify HAMLET as a new, peroral agent for colon cancer prevention and treatment, especially needed in people carrying APC mutations, where colon cancer remains a leading cause of death.

Contains fulltext : 167193.pdf (Publisher’s version ) (Open Access) Familial adenomatous polyposis (FAP) is a dominantly inherited syndrome caused by germline mutations in the APC gene and characterized by the development of multiple colorectal adenomas and a high risk of developing colorectal cancer (CRC). The severity of polyposis is correlated with the site of the APC mutation. However, there is also phenotypic variability within families with the same underlying APC mutation, suggesting that additional factors influence the severity of polyposis. Genome-wide association studies identified several single nucleotide polymorphisms (SNPs) that are associated with CRC. We assessed whether these SNPs are associated with polyp multiplicity in proven APC mutation carriers. Sixteen CRC-associated SNPs were analysed in a cohort of 419 APC germline mutation carriers from 182 families. Clinical data were retrieved from the Dutch Polyposis Registry. Allele frequencies of the SNPs were compared for patients with /=100 adenomas, using generalized estimating equations with the APC genotype as a covariate. We found a trend of association of two of the tested SNPs with the >/=100 adenoma phenotype: the C alleles of rs16892766 at 8q23.3 (OR 1.71, 95 % CI 1.05-2.76, p = 0.03, dominant model) and rs3802842 at 11q23.1 (OR 1.51, 95 % CI 1.03-2.22, p = 0.04, dominant model). We identified two risk variants that are associated with a more severe phenotype in APC mutation carriers. These risk variants may partly explain the phenotypic variability in families with the same APC gene defect. Further studies with a larger sample size are recommended to evaluate and confirm the phenotypic effect of these SNPs in FAP.

Introduction The Bowel Cancer Screening Programme in England began operating in 2006 with the aim of full roll out across England by December 2009. Subjects aged 60–69 are being invited to complete three guaiac faecal occult blood tests (6 windows) every 2 years. The programme aims to reduce mortality from colorectal cancer by 16% in those invited for screening. Methods All subjects eligible for screening in the National Health Service in England are included on one database, which is populated from National Health Service registration data covering about 98% of the population of England. This analysis is only of subjects invited to participate in the first (prevalent) round of screening. Results By October 2008 almost 2.1 million had been invited to participate, with tests being returned by 49.6% of men and 54.4% of women invited. Uptake ranged between 55–60% across the four provincial hubs which administer the programme but was lower in the London hub (40%). Of the 1.08 million returning tests 2.5% of men and 1.5% of women had an abnormal test. 17 518 (10 608 M, 6910 F) underwent investigation, with 98% having a colonoscopy as their first investigation. Cancer (n=1772) and higher risk adenomas (n=6543) were found in 11.6% and 43% of men and 7.8% and 29% of women investigated, respectively. 71% of cancers were ‘early’ (10% polyp cancer, 32% Dukes A, 30% Dukes B) and 77% were left-sided (29% rectal, 45% sigmoid) with only 14% being right-sided compared with expected figures of 67% and 24% for left and right side from UK cancer registration. Conclusion In this first round of screening in England uptake and fecal occult blood test positivity was in line with that from the pilot and the original European trials. Although there was the expected improvement in cancer stage at diagnosis, the proportion with left-sided cancers was higher than expected.

Objetivo: analizar la evolución de la mucosa rectal y del reservorio así como idoneidad de los intervalos de seguimiento y del tratamiento realizado para evitar la aparición del cáncer, en una serie de pacientes con poliposis adenomatosa familiar (PAF), intervenidos. Método: estudio prospectivo de 28 pacientes con PAF intervenidos mediante anastomosis íleo-rectal (20 pacientes) y anastomosis íleo-anal con reservorio (8 pacientes). A todos se les había realizado un control endoscópico dos veces al año y análisis del número y características macroscópicas e histológicas de los pólipos antes y después de la cirugía así como del tratamiento realizado, de sus complicaciones y de la adecuación del intervalo de seguimiento. El seguimiento medio fue de 6,47 años (DE = 4,59; rango = 0,72-16,75 años). Resultados: ninguno de los 26 pacientes que cumplimentaron correctamente el protocolo de seguimiento desarrolló cáncer. Sólo dos pacientes lo desarrollaron al 1,75 y los 3 años, respectivamente del abandono del protocolo. Los pacientes que desarrollaron adenomas durante el seguimiento fueron tratados con éxito mediante polipectomía endoscópica, salvo en dos casos que se indicó cirugía. Conclusiones: en nuestra serie, el incumplimiento de las revisiones ha sido el factor que ha condicionado la aparición de cáncer.Objective: the study was to assess changes in the rectal mucosa and pouch in a series of patients with familial adenomatous polyposis (FAP) who underwent either subtotal colectomy and ileorectal anastomosis (IRA) or proctocolectomy and ileal pouch-anal anastomosis (IPAA), and to evaluate the suitability of the follow-up interval and postoperative treatment employed to prevent the development of cancer. Method: this study involved 28 patients with FAP who underwent IRA (n=20) or IPAA (n=8), and were followed endoscopically over a mean period of 7.47 years. The number and both macroscopic and histological features of polyps before and after surgery, the treatment, and complications were all analyzed. The suitability of the follow-up interval was assessed. Results: none of the 26 patients who complied with follow-up developed rectal cancer. Two patients developed rectal cancer at 21 and 36 months after withdrawing from the protocol. Except in two cases in which surgery was indicated, patients who developed adenomas during follow-up were treated by endoscopic polypectomy. Conclusions: in our series, the failure to comply with follow-up examinations was associated with cancer development.

OBJECTIVE: Wnt signalling is critical for normal intestinal development and homeostasis. Wnt dysregulation occurs in almost all human and murine intestinal tumours and an optimal but not excessive level of Wnt activation is considered favourable for tumourigenesis. The authors assessed effects of pan-intestinal Wnt activation on tissue homeostasis, taking into account underlying physiological Wnt activity and stem-cell number in each region of the bowel. DESIGN: The authors generated mice that expressed temporally controlled, stabilised β-catenin along the crypt-villus axis throughout the intestines. Physiological Wnt target gene activity was assessed in different regions of normal mouse and human tissue. Human intestinal tumour mutation spectra were analysed. RESULTS: In the mouse, β-catenin stabilisation resulted in a graduated neoplastic response, ranging from dysplastic transformation of the entire epithelium in the proximal small bowel to slightly enlarged crypts of non-dysplastic morphology in the colorectum. In contrast, stem and proliferating cell numbers were increased in all intestinal regions. In the normal mouse and human intestines, stem-cell and Wnt gradients were non-identical, but higher in the small bowel than large bowel in both species. There was also variation in the expression of some Wnt modulators. Human tumour analysis confirmed that different APC mutation spectra are selected in different regions of the bowel. CONCLUSIONS: There are variable gradients in stem-cell number, physiological Wnt activity and response to pathologically increased Wnt signalling along the crypt-villus axis and throughout the length of the intestinal tract. The authors propose that this variation influences regional mutation spectra, tumour susceptibility and lesion distribution in mice and humans.

Objectives Capsule colonoscopy is an additional screening modality for colorectal cancer. Second-generation capsule colonoscopy (CC2) may have improved efficacy in the detection of colon adenomas as compared with prior devices. The purpose of this study was to evaluate the performance of CC2 in the detection of polyps in symptomatic and screening patients in the USA. Design Prospective, multicentre study. Setting and participants Two academic medical centres and two private practice facilities, evaluating patients with indications for colonoscopy. Methods Patients underwent capsule colonoscopy procedure using magnesium citrate as a boost, followed by colonoscopy on the same day. The main outcome measurement was accuracy of CC2 for the detection of colorectal polyps ≥6 and ≥10 mm as compared with conventional colonoscopy. Results 51 patients were enrolled, 50 of whom had CC2 and colonoscopy examinations and were included in the accuracy analysis. 30% and 14% of patients had polyps ≥6 and ≥10 mm, respectively. For lesions ≥10 mm identified on conventional colonoscopy, CC2 sensitivity was 100% (95% CI 56.1% to 100%) with a specificity of 93.0% (79.9% to 98.2%). For polyps ≥6 mm, the CC2 sensitivity was 93.3% (66.0% to 99.7%) and the specificity was 80.0% (62.5% to 90.9%). There was a 61% adequate cleansing rate with 64% of CC2 procedures being complete. Conclusions In the initial US experience with CC2 there was adequate sensitivity for detecting patients with polyps ≥6 mm in size. Magnesium citrate was inadequate as a boost agent. Trial registration number NCT01087528.

Aim To assess the positive predictive value (PPV) of CTC in the clinical routine of a dedicated referral centre. Material and methods All consecutive patients referred for CTC between May 2009 and May 2010 were considered for inclusion in this study. All the patients who, following the diagnosis of a > 6 mm polyp or mass at CTC, underwent a post-CTC colonoscopy within eight weeks from diagnosis were included. Per patient PPV for lesions, adenomas and advanced neoplasia was calculated. Chi-square test was used for statistical comparison, and a p value Results 516 patients were included in the study. Of them, 76 (14%) patients had at least one lesion ≥6 mm on CTC. Overall, 59 (11%) patients were diagnosed at CTC with at least one polyp, 12 (2%) with a flat lesions, and 5 (1%) with a mass. Per-patient PPVs for any lesion >6 mm, neoplasia, and advanced neoplasia were 96% (95% CI: 92–100%), 68.4% (95% CI: 58–79%), and 30% (95% CI: 20–41%), respectively. PPV for neoplasia and advanced neoplasia was substantially higher for >10 mm lesions. Conclusion In dedicated centers, CTC appears to be a highly specific procedure, characterized by a very low rate of false-positive results for >6 mm lesions.

Objetivo: analizar la evolución de la mucosa rectal y del reservorio así como idoneidad de los intervalos de seguimiento y del tratamiento realizado para evitar la aparición del cáncer, en una serie de pacientes con poliposis adenomatosa familiar (PAF), intervenidos. Método: estudio prospectivo de 28 pacientes con PAF intervenidos mediante anastomosis íleo-rectal (20 pacientes) y anastomosis íleo-anal con reservorio (8 pacientes). A todos se les había realizado un control endoscópico dos veces al año y análisis del número y características macroscópicas e histológicas de los pólipos antes y después de la cirugía así como del tratamiento realizado, de sus complicaciones y de la adecuación del intervalo de seguimiento. El seguimiento medio fue de 6,47 años (DE = 4,59; rango = 0,72-16,75 años). Resultados: ninguno de los 26 pacientes que cumplimentaron correctamente el protocolo de seguimiento desarrolló cáncer. Sólo dos pacientes lo desarrollaron al 1,75 y los 3 años, respectivamente del abandono del protocolo. Los pacientes que desarrollaron adenomas durante el seguimiento fueron tratados con éxito mediante polipectomía endoscópica, salvo en dos casos que se indicó cirugía. Conclusiones: en nuestra serie, el incumplimiento de las revisiones ha sido el factor que ha condicionado la aparición de cáncer. Objective: the study was to assess changes in the rectal mucosa and pouch in a series of patients with familial adenomatous polyposis (FAP) who underwent either subtotal colectomy and ileorectal anastomosis (IRA) or proctocolectomy and ileal pouch-anal anastomosis (IPAA), and to evaluate the suitability of the follow-up interval and postoperative treatment employed to prevent the development of cancer. Method: this study involved 28 patients with FAP who underwent IRA (n=20) or IPAA (n=8), and were followed endoscopically over a mean period of 7.47 years. The number and both macroscopic and histological features of polyps before and after surgery, the treatment, and complications were all analyzed. The suitability of the follow-up interval was assessed. Results: none of the 26 patients who complied with follow-up developed rectal cancer. Two patients developed rectal cancer at 21 and 36 months after withdrawing from the protocol. Except in two cases in which surgery was indicated, patients who developed adenomas during follow-up were treated by endoscopic polypectomy. Conclusions: in our series, the failure to comply with follow-up examinations was associated with cancer development.

Purpose We aimed to study the intracellular expression of 5-lipoxygenase (5-LOX), the primary competitor with cyclooxygenase-2 in arachidonic acid metabolism, as inflammatory enzymes may be involved in blocking apoptosis and promoting cancer growth by changing arachidonic acid metabolism within cells. Our purpose was to investigate the possible connection between 5-LOX expression and colon carcinogenesis by characterizing 5-LOX expression in histologically different colonic adenomas, determining the relationship between high expression of 5-LOX and various conventional clinicopathological features of adenomas, and finally characterizing the histological localization of cells with 5-LOX overexpression. Methods A total of 111 patients were examined and 120 histologically different colonic adenomas analyzed (including four cases of intramucosal adenocarcinoma in a polyp). Immunohistochemical staining with polyclonal anti-5-LOX antibodies was performed. Results There was a significant correlation between high 5-LOX expression and patient age, increased polyp size, high grade of intraepithelial neoplasia, villous and tubulovillous adenoma, and histological epithelial localization. Conclusions We observed a strong positive correlation between 5-LOX overexpression and the appearance of typical high-risk factors for malignant transformation in adenomatous polyps. The results support the role of 5-LOX in early stages of colon carcinogenesis.