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Featured researches published by Christian Pox.


Endoscopy | 2013

Post-polypectomy colonoscopy surveillance: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

Cesare Hassan; Enrique Quintero; Jean-Marc Dumonceau; Jaroslaw Regula; Catarina Brandão; Stanislas Chaussade; Evelien Dekker; Mário Dinis-Ribeiro; Monika Ferlitsch; Antonio Z. Gimeno-García; Yark Hazewinkel; Rodrigo Jover; Mette Kalager; Magnus Løberg; Christian Pox; B. Rembacken; David A. Lieberman

MAIN RECOMMENDATIONS The following recommendations for post-polypectomy endoscopic surveillance should be applied only after a high quality baseline colonoscopy with complete removal of all detected neoplastic lesions.1 In the low risk group (patients with 1 - 2 tubular adenomas < 10 mm with low grade dysplasia), the ESGE recommends participation in existing national screening programmes 10 years after the index colonoscopy. If no screening programme is available, repetition of colonoscopy 10 years after the index colonoscopy is recommended (strong recommendation, moderate quality evidence). 2 In the high risk group (patients with adenomas with villous histology or high grade dysplasia or ≥10 mm in size, or ≥ 3 adenomas), the ESGE recommends surveillance colonoscopy 3 years after the index colonoscopy (strong recommendation, moderate quality evidence). Patients with 10 or more adenomas should be referred for genetic counselling (strong recommendation, moderate quality evidence). 3 In the high risk group, if no high risk adenomas are detected at the first surveillance examination, the ESGE suggests a 5-year interval before a second surveillance colonoscopy (weak recommendation, low quality evidence). If high risk adenomas are detected at first or subsequent surveillance examinations, a 3-year repetition of surveillance colonoscopy is recommended (strong recommendation, low quality evidence).4 The ESGE recommends that patients with serrated polyps < 10 mm in size with no dysplasia should be classified as low risk (weak recommendation, low quality evidence). The ESGE suggests that patients with large serrated polyps (≥ 10 mm) or those with dysplasia should be classified as high risk (weak recommendation, low quality evidence).5 The ESGE recommends that the endoscopist is responsible for providing a written recommendation for the post-polypectomy surveillance schedule (strong recommendation, low quality evidence).


The American Journal of Gastroenterology | 2005

Feasibility and Diagnostic Utility of Video Capsule Endoscopy for the Detection of Small Bowel Polyps in Patients with Hereditary Polyposis Syndromes

Karsten Schulmann; Stephan Hollerbach; Katja Kraus; Jörg Willert; T Vogel; Gabriela Möslein; Christian Pox; Markus Reiser; Anke Reinacher-Schick; Wolff Schmiegel

OBJECTIVES:At present, surveillance of premalignant small bowel polyps in hereditary polyposis syndromes has a number of limitations. Capsule endoscopy (CE) is a promising new method to endoscopically assess the entire length of the small bowel.METHODS:We prospectively examined 40 patients with hereditary polyposis syndromes (29 familial adenomatous polyposis (FAP), 11 Peutz-Jeghers syndrome (PJS)). Results were compared with push-enteroscopy (PE) results in FAP and with esophagogastroduodenoscopy, PE, (MR)-enteroclysis, and surgical specimen in PJS patients.RESULTS:A total of 76% of the patients with FAP with duodenal adenomas (n = 21) had additional adenomas in the proximal jejunum that could be detected by CE and PE. Moreover, 24% of these FAP patients had further polyps in the distal jejunum or ileum that could only be detected by CE. In contrast, in FAP patients without duodenal polyps (n = 8), jejunal or ileal polyps occurred rarely (12%). CE detected polyps in 10 of 11 patients with PJS, a rate superior to all other reference procedures employed. Importantly, the findings of CE had immediate impact on further clinical management in all PJS patients.CONCLUSIONS:Our results suggest that CE may be of clinical value in selected patients with FAP, whereas in PJS, CE could be used as first line surveillance procedure.


Gastroenterology | 2012

Efficacy of a Nationwide Screening Colonoscopy Program for Colorectal Cancer

Christian Pox; Lutz Altenhofen; Hermann Brenner; Arno Theilmeier; Dominik von Stillfried; Wolff Schmiegel

BACKGROUND & AIMS Screening colonoscopy examinations for colorectal cancer are offered in the United States and some European countries. Data on results and adverse effects of screening colonoscopy are limited. In autumn 2002, colonoscopy was introduced as part of a nationwide cancer screening program in Germany; it was offered to the general population for individuals 55 years of age or older. We collected and analyzed data from this program. METHODS We performed a prospective cross-sectional study, collecting results from 2,821,392 screening colonoscopies performed at more than 2100 practices by highly qualified endoscopists in Germany from January 2003 to December 2008. Data on participation, colorectal adenoma and cancer detection, and complications were collected using standardized documentation forms. The data generated were centrally processed and evaluated. RESULTS The cumulative participation rate was 17.2% of eligible women and 15.5% of eligible men 55-74 years old. The adenoma detection rate (ADR) was 19.4%, with a higher rate in men (25.8% vs 16.7% in women). Advanced adenomas were found in 6.4% of patients. Carcinomas were detected in 25,893 subjects (0.9%); most were of an early UICC stage (I, 47.3%; II, 22.3%; III, 20.7%; IV, 9.6%). The ADRs for gastroenterologists and nongastroenterologists were 25.1% and 22.3%, respectively (adjusted odds ratio, 1.18; 95% confidence interval, 1.16-1.21). The overall complication rate was 2.8/1000 colonoscopies, and the rate of serious complications was 0.58/1000 colonoscopies. CONCLUSIONS A nationwide colonoscopy screening program that uses highly qualified endoscopists can detect a significant number of adenomas and early-stage carcinomas. The ADR for gastroenterologists was higher than for nongastroenterologists.


Zeitschrift Fur Gastroenterologie | 2010

S3 Guidelines for Colorectal Carcinoma

Wolff Schmiegel; Christian Pox; Anke Reinacher-Schick; G. Adler; Dirk Arnold; W. Fleig; U. R. Fölsch; P. Frühmorgen; Ullrich Graeven; Volker Heinemann; Werner Hohenberger; Holstege A; T. Junginger; I. Kopp; T. Kühlbacher; Rainer Porschen; Propping P; J.-F. Riemann; Claus Rödel; Rolf Sauer; T. Sauerbruch; W. Schmitt; Hans-Joachim Schmoll; Thomas Seufferlein; Zeitz M; Selbmann Hk

Correspondence Prof. Dr. Wolff Schmiegel Medizinische Klinik, Ruhr-Universität Bochum, Knappschaftskrankenhaus In der Schornau 23–25 44892 Bochum Tel.: ++ 49/2 34/2 993401 Fax: ++ 49/2 34/2 9934 09 [email protected] www.medunikkh.de Representing the German Society for Digestiveand Metabolic Diseases (DGVS) and the German Cancer Society (DKG) In collaboration with the: ▶ German Society for Visceral Surgery (DGVC) ▶ German Society for Haematology and Oncology (DGHO) ▶ German Society of Pathology (DGP) ▶ German Society of Radio-oncology (DEGRO) ▶ Surgical Working Group for Oncology abdominal surgery (CAO-V) ▶ Germany Radiological Society (DRG) ▶ German Combined Society for Clinical Chemistry and Laboratory Medicine (DGKL) ▶ German Society of Coloproctology (DGK) ▶ Association for Stoma Patients and Persons with Colorectal Cancer (German ILCO) ▶ German Crohn’s Disease and Ulcerative colitis Association (DCCV) ▶ German Society of Internal Medicine (DGIM) ▶ Working Group for Scientific Medical Specialised Societies e.V. (AWMF) ▶ with support from the German Cancer Society e.V. (DKH) Directors 2004: W. Schmiegel, H.-K. Selbmann Leadership Update 2008: W. Schmiegel with the collaboration of: C. Pox, A. Reinacher-Schick, I. Kopp


International Journal of Cancer | 2006

Novel strategy for optimal sequential application of clinical criteria, immunohistochemistry and microsatellite analysis in the diagnosis of hereditary nonpolyposis colorectal cancer.

Christoph Engel; Jochen Forberg; Elke Holinski-Feder; Constanze Pagenstecher; Jens Plaschke; Matthias Kloor; Christopher Poremba; Christian Pox; Josef Rüschoff; Gisela Keller; Wolfgang Dietmaier; Petra Rümmele; Nicolaus Friedrichs; Elisabeth Mangold; Reinhard Buettner; Hans K. Schackert; Peter Kienle; Susanne Stemmler; Gabriela Moeslein; Markus Loeffler

Clinical criteria, microsatellite analysis (MSA) and immunohistochemistry (IHC) are important diagnostic tools for identification of hereditary nonpolyposis colorectal cancer (HNPCC) patients who are likely to carry pathogenic germline mutations in mismatch repair genes. Based on MSA and IHC results and subsequent mutation analyses of 1,119 unrelated index patients meeting the Amsterdam II criteria or the classical Bethesda guidelines, we analyzed the value of these tools to predict MLH1 and MSH2 mutations with the aim of establishing optimal strategies for their most efficient sequential use. The overall prevalence of pathogenic germline mutations in our cohort was 20.6% (95% CI = 18.3–23.0%) and 61.8% (95% CI = 56.8–66.6%), respectively, after MSA/IHC‐based preselection. IHC was highly predictive (99.1%) and specific (99.6%) with regard to MSA. However, 14 out of 230 mutations (6%) escaped detection by IHC. Thus, IHC cannot be recommended to substitute MSA fully. Nonetheless, IHC is important to indicate the gene that is likely to be affected. To combine both methods efficiently, we propose a novel screening strategy that provides 2 alternative ways of sequential IHC and MSA application, either using IHC or MSA in the first place. A logistic regression model based on the age of the index patient at first tumor diagnosis and the number of fulfilled HNPCC criteria is used to allocate individual patients to that alternative pathway that is expected to be least expensive. A cost analysis reveals that about 25% of the costs can be saved using this strategy.


International Journal of Colorectal Disease | 2010

Truncating mutations in Peutz-Jeghers syndrome are associated with more polyps, surgical interventions and cancers.

Heidi Salloch; Anke Reinacher-Schick; Karsten Schulmann; Christian Pox; Jörg Willert; Andrea Tannapfel; Stefan Heringlake; Timm O. Goecke; Stefan Aretz; Susanne Stemmler; Wolff Schmiegel

Background and GoalsPeutz-Jeghers syndrome (PJS) is a rare autosomal dominant polyposis syndrome caused by STK11 germline mutations. PJS is associated with an increased risk of cancer. In our cohort, clinical and phenotypic parameters were correlated with genotypic findings and patients were prospectively followed by surveillance.StudyThirty-one patients treated between 2000 and 2006, were evaluated. STK11 genotyping was performed and phenotypes of patients with truncating (TM) and nontruncating mutations (NTM) were compared.ResultsMedian age at first symptoms was 11 years and complications occurred before the age of ten in 42% of patients. STK11 mutations were detected in 16 of 22 families (12 TM; four NTM). Patients with TM had more surgical gastrointestinal (GI) interventions (p = 0.021), and female patients in the TM group had an increased risk of undergoing gynecological surgery (p = 0.016). Also, there was a trend towards a higher polyp count (p = 0.11) and earlier age at first polypectomy (p = 0.13) in the TM group. Ten carcinomas were detected in six patients resulting in a cancer risk of 65% up to the age of 65 years. Patients with TM tended to develop more cancers (p = 0.10). Importantly, our surveillance strategy used detected 50% of cancers (n = 5) at an early potentially curable stage.ConclusionsOur study shows that almost half of PJ patients have complications early in life independent of mutational status. Patients with TM require more surgical GI interventions and tend to develop more polyps and cancers. Furthermore, close surveillance detects early stage cancers in patients. We propose that surveillance should be started as early as 8 years in all patients to avoid complications. Moreover, patients with TM may benefit from surveillance at shorter intervals.


Gut | 2010

Role of CT colonography in colorectal cancer screening: risks and benefits

Christian Pox; Wolff Schmiegel

The purpose of this article is to review recent developments in the role of CT colonography with an emphasis on colorectal cancer screening. An introduction to the concept and method of CT colonography is given as well as a summary of the data on performance of CT colonography. Furthermore, details on side effects, efficacy and cost-effectiveness and the possible role of extracolonic findings are provided. The impact CTC could have on colonoscopy and other possible indications of the method are also mentioned.


Deutsches Arzteblatt International | 2009

Colorectal carcinoma: the management of polyps, (neo)adjuvant therapy, and the treatment of metastases.

Wolff Schmiegel; Christian Pox; Dirk Arnold; Rainer Porschen; Claus Rödel; Anke Reinacher-Schick

BACKGROUND Colorectal carcinoma (CRC) is the second most common type of cancer in Germany. In view of recent major changes in the diagnosis and treatment of CRC, the S3 guideline for CRC published in its full version in 2004 was partially updated in 2008 and again in 2009. METHOD The literature was systematically searched for all articles published from 2004 onward concerning polyp management, (neo-)adjuvant treatment, and treatment of metastatic disease. Evidence-based recommendations were developed in a consensus conference. RESULTS For some patients who have undergone polypectomy, the time to follow-up with colonoscopy can be lengthened. In UICC stage III colon cancer, adjuvant chemotherapy with an oxaliplatin-based regimen is recommended. In stage II colon cancer, adjuvant chemotherapy should be considered mainly when risk factors are present. In stages II and III, neo-adjuvant therapy should be given before resection in rectal cancer. In patients with metastatic disease, the use of all possible treatment options results in a median overall survival time of 24 months. In some patients with primarily non-resectable liver metastases, systemic treatment may enable a secondary, potentially curative resection. Therapeutic agents are chosen individually on the basis of clinical factors including the goal of treatment, the patients general condition, and tumor molecular markers. CONCLUSION The S3 guideline contains evidence-based recommendations for the diagnosis and treatment of colorectal carcinoma. Broad implementation of the guideline will be essential for improved patient care.


International Journal of Cancer | 2014

Evaluating the performance of clinical criteria for predicting mismatch repair gene mutations in Lynch syndrome: A comprehensive analysis of 3,671 families

Verena Steinke; Stefanie Holzapfel; Markus Loeffler; Elke Holinski-Feder; Monika Morak; Hans K. Schackert; Heike Görgens; Christian Pox; Brigitte Royer-Pokora; Magnus von Knebel-Doeberitz; Reinhard Büttner; Peter Propping; Christoph Engel

Carriers of mismatch repair (MMR) gene mutations have a high lifetime risk for colorectal and endometrial cancers, as well as other malignancies. As mutation analysis to detect these patients is expensive and time‐consuming, clinical criteria and tumor‐tissue analysis are widely used as pre‐screening methods. The aim of our study was to evaluate the performance of commonly applied clinical criteria (the Amsterdam I and II Criteria, and the original and revised Bethesda Guidelines) and the results of tumor‐tissue analysis in predicting MMR gene mutations. We analyzed 3,671 families from the German HNPCC Registry and divided them into nine mutually exclusive groups with different clinical criteria. A total of 680 families (18.5%) were found to have a pathogenic MMR gene mutation. Among all 1,284 families with microsatellite instability‐high (MSI‐H) colorectal cancer, the overall mutation detection rate was 53.0%. Mutation frequencies and their distribution between the four MMR genes differed significantly between clinical groups (p < 0.001). The highest frequencies were found in families fulfilling the Amsterdam Criteria (46.4%). Families with loss of MSH2 expression had higher mutation detection rates (69.5%) than families with loss of MLH1 expression (43.1%). MMR mutations were found significantly more often in families with at least one MSI‐H small‐bowel cancer (p < 0.001). No MMR mutations were found among patients under 40‐years‐old with only colorectal adenoma. Familial clustering of Lynch syndrome‐related tumors, early age of onset, and familial occurrence of small‐bowel cancer were clinically relevant predictors for Lynch syndrome.


Digestive Diseases | 2011

Colon Cancer Screening: Which Non-Invasive Filter Tests?

Christian Pox

The following non-invasive stool tests for colorectal cancer (CRC) screening exist: guaiac or immunochemical fecal occult blood testing (FOBT), genetic stool tests and the M2-PK. Currently the most widely used tests are guaiac-based (gFOBT). Several randomized controlled trials have shown that gFOBT are able to achieve a reduction in CRC-related mortality. This reduction is achieved by detecting asymptomatic cancers at an early stage with a better prognosis. However, gFOBT have a low sensitivity for colorectal adenomas and are thus unlikely to be able to reduce the incidence of CRC. Furthermore, gFOBT are not specific for human blood and can be influenced by external factors. Immunochemical tests (iFOBT) only detect human blood in the stool. In two recent randomized studies from the Netherlands comparing guaiac and immunochemical tests in the asymptomatic population, iFOBT were found to detect more cancers than gFOBT. Furthermore, iFOBT were able to detect more advanced adenomas thus having the potential to be able to reduce the incidence of CRC as well as CRC-related mortality. In the recently released European CRC screening guidelines, iFOBT are considered the screening test of choice. Several questions remain however. It is currently unknown what the optimal cut-off value for an iFOBT to be considered positive should be and what the number of stool samples is that are required. Genetic stool tests detect mutations in stool that can be found in CRC. The original test testing for 21 genetic changes was found to be superior to gFOBT for the detection of cancers. However, the sensitivity was moderate (51.6%) and the sensitivity for advanced adenomas was low. In the meantime the test has been modified improving DNA extraction and reducing the number of mutations tested for as well as including a methylation marker. The efficacy of the modified test in the screening population is unknown. M2-PK is an isomer of the enzyme pyruvate kinase that is involved in glycolysis. Studies have found a good sensitivity for cancers, a low sensitivity for advanced adenomas with a specificity of around 80%. Further studies in the screening population are required.

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Hans K. Schackert

Dresden University of Technology

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Nils Rahner

University of Düsseldorf

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