Randomized experimental study of two novel techniques for transanal repair of dehiscent low rectal anastomosis.

BACKGROUND: Anastomotic leak after low anterior rectal resection is a dreadful complication. Early diagnosis, prompt management of sepsis followed by closure of anastomotic defect may increase chances of anastomotic salvage. In this randomized experimental study, we evaluated two different methods of trans-anal anastomotic repair. METHODS: A model of anastomotic leak was created in 42 male pigs. Laparoscopic low anterior resection was performed with anastomosis created using a circular stapler with half of the staples removed. Two days later, animals were randomized into a TAMIS (trans-anal minimally invasive surgery) repair, endoscopic suture (ENDO) or control group with no treatment (CONTROL). Signs of intraabdominal infection (IAI), macroscopic anastomotic healing and burst tests were evaluated to assess closure quality after animals were sacrificed on the ninth postoperative day. RESULTS: Closure was technically feasible in all 28 animals. Two animals had to be euthanized due to progressive sepsis at four and five days after endoscopic closure. Healed anastomosis with no visible defect was observed in 10/14 and 11/14 animals in TAMIS and ENDO groups, respectively, versus 2/14 in CONTROL (p < 0.05). Overall IAI rate was significantly lower in TAMIS (4/14; p = 0.006) and ENDO (5/14; p = 0.018) compared to CONTROL (12/14). Burst tests confirmed sealed closure in healed anastomosis with a median failure pressure of 190 (110-300) mmHg in TAMIS and 200 (100-300) mmHg in ENDO group (p = 0.644). CONCLUSION: In this randomized experimental study, we found that both evaluated techniques are effective in early repair of dehiscent colorectal anastomosis with a high healing rate.

Confocal laser endomicroscopy in diagnosing indeterminate biliary strictures and pancreatic lesions a prospective pilot study.

INTRODUCTION: An accurate histopathological diagnosis of indeterminate biliary strictures and pancreatic lesions is challenging because of insufficient quali-ty of tissue specimen taken during ERCP (brush cytology), cholangioscopy (biopsies) or endosonography (EUS, FNAB). Confocal laser endomicroscopy (CLE) allows virtual histopathological diagnosis with the potential to either replace or increase the diagnostic yield of standard histopathological diagnosis in patients presenting with biliary strictures and pancreatic lesions. The aims of our prospective pilot study were to: 1. Assess the diagnostic yield of standard histopathology compared to CLE in patients referred for cholangioscopy or for EUS of the pancreas; 2. Evaluate the cost of CLE in these indications. METHODS: CLE was performed (during cholangioscopy or EUS), followed by standard tissue sampling. CLE-based diagnosis was compared with standard histopathology/cytology. CLE probe was introduced through the working channel of the cholangioscope or through the FNAB needle. RESULTS: A total of 23 patients were enrolled (12 women, mean age 61 years); 13 patients underwent cholangioscopy and 10 patients underwent EUS. Cholangioscopy: CLE diagnosed correctly all 4 malignant strictures (histology 2 of them only as 2 patients had insufficient quality of the tissue specimen). Agreement between standard histopathology and CLE was achieved in 85 %. EUS: All 3 cases of pancreatic cancer were correctly diagnosed by both CLE and FNAB. All remaining (premalignant and benign) lesions were also correctly diagnosed by both methods. The cost of CLE examination is higher compared to FNAB but comparable with tissue sampling during digital cholangioscopy. CONCLUSION: CLE demonstrated sufficient diagnostic accuracy in patients with indeterminate biliary strictures or pancreatic lesions and, therefore, might improve diagnostic accuracy or even replace standard histopathology in these indications.

The experience with colorectal cancer screening in the Czech Republic: the detection at earlier stages and improved clinical outcomes.

OBJECTIVES: Colorectal cancer (CRC) remains a major health burden. Although screening is recommended and considered beneficial, further data on its positive effects are needed for worldwide implementation. STUDY DESIGN: The aim of our national multicentre prospective observational study was to reveal and document clinicopathological differences in CRC diagnosed by screening and presented by disease symptoms as well as assess the efficiency of the screening programme in the Czech Republic. METHODS: Between March 2013 and September 2015, a total of 265 patients were enrolled in 12 gastroenterology centres across the Czech Republic. Patients were divided into screening and symptomatic groups and compared for pathology status and clinical characteristics. Screening was defined as a primary screening colonoscopy or a colonoscopy after a positive faecal occult blood test in an average-risk population. RESULTS: The distribution of CRC stages was significantly (statistically and clinically) favourable in the screening group (predominance of stages 0, I and II) compared with the non-screening group (P < 0.001). The presence of distant and local metastases was significantly less frequent in the screening group than in the symptomatic group (P < 0.001). Patients in the screening group had a higher probability of radical surgery (R0) than those diagnosed based on symptoms (P < 0.001). Systemic palliative treatment was indicated in two patients in the screening group compared with 23 patients in the non-screening group (P = 0.018). CONCLUSION: CRC diagnosed by screening disclosed less advanced clinicopathological characteristics and results in patients with a higher probability of radical surgery (R0) than diagnoses established based on symptoms, with subsequent management differing accordingly between both groups. These results advocate the implementation of a suitable worldwide screening programme.

NOTES in Europe: summary of the working group reports of the 2012 EURO-NOTES meeting.

The sixth EURO-NOTES workshop (4 - 6 October 2012, Prague, Czech Republic) focused on enabling intensive scientific dialogue and interaction between surgeons, gastroenterologists, and engineers/industry representatives and discussion of the state of the practice and development of natural orifice transluminal endoscopic surgery (NOTES) in Europe. In accordance with previous meetings, five working groups were formed. In 2012, emphasis was put on specific indications for NOTES and interventional endoscopy. Each group was assigned an important indication related to ongoing research in NOTES and interventional endoscopy: cholecystectomy and appendectomy, therapy of colorectal diseases, therapy of adenocarcinoma and neoplasia in the upper gastrointestinal tract, treating obesity, and new therapeutic approaches for achalasia. This review summarizes consensus statements of the working groups.

[Evaluation of variants of unknown significance in the BRCA2 gene]. / Hodnocení variant nejasného významu v genu BRCA2.

BACKGROUND: Endogenous processes and exogenous agents cause constant DNA damage. DNA double-strand breaks are among the most serious types of damage. They are mainly repaired by homologous recombination, where the BRCA2 protein plays a dominant role. Heterozygous germline BRCA2 mutations predispose to breast, ovarian, pancreatic and other types of cancer. The presence of a pathogenic mutation in patients or their family members warrants close surveillance and prophylactic surgery. Apart from clearly pathogenic mutations, variants leading only to a single amino acid substitution are often identified. Since the influence of these variants on cancer risk is unknown, they represent a major clinical problem. AIMS: The aim of this paper is to summarize the current possibilities of predicting pathogenicity of BRCA2 variants. In some cases, genetic methods are able to classify variants with high probability; however, their use is often limited by low frequency of the variants or inaccessibility of samples for mRNA isolation or DNA from family members. Alternatively, functional assays performed in various cellular models may be employed. Multiple functional tests and cellular models are presented and characterized, including their advantages and limitations. A new model of human syngeneic cell lines developed by the authors is presented, in which one BRCA2 allele is deleted and the variant is introduced into the other allele by homologous recombination. This model has the potential to evaluate function of variants without some of the unwanted effects of the other models. Currently, this model is being applied to variants identified in patients with hereditary cancer predisposition in the Masaryk Memorial Cancer Institute. CONCLUSION: Functional assays in cellular models including a new model of syngeneic cell lines described by the authors have a great potential in evaluating clinical importance of unclassified variants in the BRCA2 gene, especially in cases where genetic tests are not applicable.

[A detailed study of colon polyps]. / Podrobná studie o polypech tlustého streva.

UNLABELLED: INTRODUCTION, STUDY AIM: Colorectal carcinoma is one of the most frequent malignancies. Most frequently, neoplasms, including malignant precursors, are in the form of polyps, although these might be of a non-tumour origin. The aim of this prospective multicentre study was to provide an overview of coloscopic identification and biological nature of polyps. RESULTS: 3,400 consecutive coloscopies performed between 2009 and 2010 were analyzed. At different centres, the top of the cecum was reached in 89% to 93% and terminal ileum in 73% to 87% of cases. In the above 40 age group, 26.6% were screening coloscopies. The mean age of the above 40 patients was 56 years. The incidence of potential neoplastic lesions (polyps, carcinomas), advanced adenomas and carcinomas were: 7.8 %, 0.8 % and 0.16 %, respectively, in the above 40 age group, 41.5 %, 9.8 % and 1.6 %, respectively, in the 40-50 years age group and 70.5 %, 31.3 % and 6.8 %, respectively, in the above 50 age group. The incidence of tubular adenoma and hyperplastic polyps was 23.9% and 66.2%, respectively, in the below 40 age group and 53.1% and 26.1% in the above 50 age group. 57.8% of advances neoplasms were located in the rectosigmoid a descendent colon. The incidence ratio for adenomas and hyperplastic polyps was 76.6% and 14%, respectively, for rectosigmoid colon, 63.6 and 17.4 %, respectively, for descendent colon, 63.6 and 11.4 % for traverse colon and 63,4 a 17,9 %, respectively, for cecum and ascendant colon. The incidence of tubulovillous adenomas and hyperplastic polyps in pedunculated polyps larger than 1 cm was 19.4 % and 20.4 %, respectively, and 34.2 % and 13.1 %, respectively, in other polyps. The incidence of potential lesions (polyps and carcinomas), advanced adenomas, carcinomas and advanced neoplasms was 66.7 %, 23.1 %, 5.8 % and 28.9 %, respectively, in women and 63.1 %, 30.0 %, 5.7 % and 34.7 %, respectively, in men. CONCLUSION: The top of the cecum was reached in a higher proportion of cases than required, although this was lower than in the majority of other recent studies. Terminal ileum was reached in high number of cases. The incidence of polyps and neoplasms rose sharply from 40 years of age. Therefore, the screening threshold should be extended to the below 50 age group. Hyperplastic polyps predominated in younger age and adenomas in the above 40 age group. Histological profile was similar and did not suggest importantly different pathogenesis with respect to localization. There were relatively fewer adenomas and more hyperplastic polyps in pedunculated polyps and vice verse in other types of polyps, suggesting a higher risk associated with non-pedunculated lesions. Both sexes differed less than suggested based on epidemiological statistics.

DNA repair: exploiting the Fanconi anemia pathway as a potential therapeutic target.

DNA repair is an active cellular process to respond to constant DNA damage caused by metabolic processes and environmental factors. Since the outcome of DNA damage is generally adverse and long term effects may contribute to oncogenesis, cells have developed a variety of DNA repair mechanisms, which operate depending on the type of DNA damage inflicted. At least 15 Fanconi anemia (FA) proteins interact in a common pathway involved in homologous recombination. Inherited homozygous mutations in any of these FA genes cause a rare disease, Fanconi anemia, characterized by congenital abnormalities, progressive bone-marrow failure and cancer susceptibility. Heterozygous germline FA mutations predispose to various types of cancer. In addition, somatic FA mutations have been identified in diverse cancer types. Evidence exists that cells deficient in the FA pathway become dependent on alternative pathways for survival. Additional inhibition of such alternative pathways is thus expected to result in cell death, creating a relationship of synthetic lethality. Identifying these relationships can reveal yet unknown mechanisms of DNA repair and new targets for therapy.

Low incidence of adenocarcinoma and high-grade intraepithelial neoplasia in patients with Barrett's esophagus: a prospective cohort study.

BACKGROUND AND STUDY AIMS: Barrett's esophagus is a premalignant condition. The risk of developing high grade intraepithelial neoplasia (HGIN) or adenocarcinoma is currently a matter of debate. Due to several shortcomings, previous studies have probably overestimated the risk. The main aim of our study was to investigate the incidence of HGD and adenocarcinoma in a cohort of patients with Barrett's esophagus. PATIENTS AND METHODS: In a prospective, cohort study, all patients had intestinal metaplasia and macroscopic evidence of short- or long-segment (< 3 cm or > or = 3 cm) Barrett's esophagus. All patients underwent a standard protocol including regular endoscopies with biopsies and were treated with a proton pump inhibitor or antireflux surgery. RESULTS: A total of 135 patients underwent 623 endoscopies during 700 patient-years (mean follow-up 5.2 +/- 2.3 years). Simultaneous HGIN and adenocarcinoma were detected in two patients with long-segment Barrett's esophagus (1.5%; 2 and 6 years after the index endoscopy). Low grade intraepithelial neoplasia (LGIN) was detected in 25 patients (18.5%); in 11 of these patients (44%), LGIN was not confirmed in later biopsies. Our study shows an incidence of HGIN/adenocarcinoma of 1/350 patient-years. Endoscopic regression of Barrett's esophagus was seen in 20.7% of patients. CONCLUSION: The incidence of HGIN/adenocarcinoma is low in patients with adequately treated Barrett's esophagus. The annual risk of developing HGIN/adenocarcinoma is 0.21% (1.6% in long-segment Barrett's esophagus).

Pancreaticobiliary malunion and incomplete pancreas divisum: an unusual cause of common bile duct obstruction.

PURPOSE: Pancreaticobiliary malunion (PBM) is a distinct disease entity of the pancreatic and biliary ductal system defined as a condition in which the junction of the pancreatic and biliary ducts occurs above the duodenal wall. PBM may be combined with a stenosis of the distal common bile duct and pathological changes in the common bile duct wall (congenital cyst of bile duct), being a potentially malignant condition. Pancreas divisum, resulting from a fusion failure of the ventral and dorsal pancreatic buds, and characterized by a dominant Santorine duct, is considered to be a predisposing factor to recurrent attacks of acute pancreatitis. In incomplete pancreas divisum, the ventral and dorsal pancreas are connected by a segmental branch. MATERIAL AND METHODS: We report a case of a 33-year-old female patient with PBM associated with incomplete pancreas divisum, who had presented episodes of acute cholangitis due to a benign distal common bile duct stricture. RESULTS: Treatment with choledochoduodenostomy and cholecystectomy provided thorough relief and resolution of symptoms. CONCLUSION: This is the first report of coexistent PBM and incomplete pancreas divisum in a Caucasian patient with unusually late clinical manifestation.