Browsing by Author "Langer, C."

The treatment of comminuted fractures of the radial head with concomitant injuries of the ulnar complex by resection of the radial head usually does not provide satisfactory long-term results. Other than joint instability in the elbow and a limited range of motion, radius proximalisation in the sense of ulnocarpal impingement, osteoarthritis and pain in the elbow have been described. Between 1995 and 1997, 11 radial head prostheses were implanted in ten patients who had sustained a comminuted fracture of the radial head with concomitant injury to the ulnar complex. A follow-up survey was conducted with the patients on average 5 years after the injury. Eight patients with nine implants participated in the follow-up, one patient had died and another refused to participate but declared that he did not suffer from any impairment. According to the Morrey score, two of the results were found to be very good,five to be good, one to be fair and one to be poor. Despite the severe injuries sustained by the elbow, neither joint instability in the elbow nor proximalisation of the radius, cubitus valgus, ulnar nerve syndrome, nor loosening of the prosthesis were found in any of the patients. In the event of comminuted fractures of the radial head which are impossible to reconstruct by osteosynthesis and which occur with concomitant ulnar ligamentous or osseous injury, the implantation of a prosthesis is preferred over the resection of the head of the radius.

The course in Gastrointestinal Surgery (GISC) aims at teaching and training resection, reconstruction and suture techniques of the upper gastrointestinal tract. Prior to, after and 5 years following the first course, participants were asked to answer a questionnaire requesting information regarding the adequacy of surgical training in their residency program and how much they had benefited from the GISC. While 1/3 of the participants described the surgical training during their residency as inadequate, more than 90% benefited from the GISC. Although the single-layer-continuous suture technique was implemented by only 8% of the participating surgeons, other techniques such as cross-section gastroenterostomy were accepted by 38%. Only 7% of the participants rejected these new techniques, while 41% of the senior surgeons at home could not be convinced. Besides the teaching of new techniques, participants benefited above all from the repetitive training in surgical procedures.

To model the cytogenetic evolution in gastrointestinal stromal tumour (GIST), an oncogenetic tree model was reconstructed using comparative genomic hybridization data from 203 primary GISTs (116 gastric and 87 intestinal GISTs, including 151 newly analysed cases), with follow-up available in 173 cases (mean 40 months; maximum 133 months). The oncogenetic tree model identified three major cytogenetic pathways: one initiated by -14q, one by -1p, and another by -22q. The -14q pathway mainly characterized gastric tumours with predominantly stable karyotypes and more favourable clinical course. On the other hand, the -1p pathway was more characteristic of intestinal GISTs, with an increased capacity for cytogenetic complexity and more aggressive clinical course. Loss of 22q, more closely associated with -1p than -14q, appeared to initiate the critical transition to an unfavourable cytogenetic subpathway. This -22q pathway included accumulation of +8q, -9p, and -9q, which could all predict disease-free survival in addition to tumour site. Thus, insights into the cytogenetic evolution obtained from oncogenetic tree models may eventually help to gain a better understanding of the heterogeneous site-dependent biological behaviour of GISTs. Copyright (c) 2007 Pathological Society of Great Britain and Ireland.

We report cytogenetic findings in 19 c-Kit-positive gastrointestinal stromal tumors (GISTs) that represent a heterogenous group of mesenchymal neoplasms with respect to site, histology, and biologic behavior. All of the GISTs (5 low-risk, 11 high-risk, 3 recurrences) displayed clonal chromosomal aberrations; 15 were hypo- to near-diploid, and 4 were near-triploid and hypotetraploid. The most common abnormalities were loss of chromosomes 14 and/or 22, demonstrated in 14 GISTs irrespective of site or predominant phenotype. Ten cases (2 low-risk, 5 high-risk, 3 recurrences) were characterized by loss of both chromosomes 14 and 22, 2 cases (1 low-risk, 1 high-risk), by loss of chromosome 14; and 2 high-risk cases, by loss of chromosome 22. Additional chromosomal aberrations occurred preferentially in high-risk and recurrent GISTs, including loss of 9p and 1p, in 8 cases each, loss of 15 in 6 cases, loss of 3p in 5 cases, loss of 13q and 10q in 4 cases each, loss of 19 in 3 cases, and complete or partial gains of chromosomes 5 and 4 in 2 cases each. More significantly, 5 of 6 patients with clinically aggressive GISTs, including 2 recurrences and 3 metastasing GISTs, were additionally characterized by loss of 9p; four of these had additional loss of chromosomes 1p and 15. The presented results herein indicate that loss of chromosome 14 and/or 22 is an early change in GIST tumorigenesis irrespective of site or differentiation, whereas malignant transformation and progression of GISTs appear to be associated with an increasing incidence of additional secondary aberrations. Copyright 2002, Elsevier Science (USA). All rights reserved.

Introduction. Body-packers or "mules" are drug smugglers who swallow cocaine-filled condoms in order to conceal them during air travel. Body pushers hide drug packages in the rectum or vagina. In a cooperative effort between the Frankfurt Airport Clinic and the GIZ-Nord (Goettingen University poison control center), we performed a retrospective study and developed an algorithm for the problem of "rupture of a cocaine-filled condom in a body-packer." Methods. In a retrospective analysis, the data of all cocaine body-packers and body pushers who were identified at Frankfurt International Airport from 1985 to 2001 were evaluated. Temporal development, demographic data, and surgical aspects were of special interest. Results. From 1985 to 2001 a total of 280 body pushers and 2880 body-packers were identified: 63 "mules" (2.2%) developed symptoms of severe cocaine intoxication following rupture of a condom. Emergency laparotomy was performed on 20 patients (i.e., 32% of all symptomatic body-packers) and the condoms were removed,while 43 body-packers (68%) died before surgical therapy could be initiated. All operated patients survived. Conclusion. Severe cocaine intoxication is life threatening. Patients die from complications caused by generalized vasoconstriction. If the reason for severe cocaine intoxication is the rupture of a cocaine-filled condom,the only possible therapy consists of immediate laparotomy for removal of the condoms.

Meckel's diverticulitis is a rare disease. In addition to physical examination, abdominal ultrasound can help to pinpoint the diagnosis. By presenting a case report we would like to demonstrate the typical ultrasonographic findings in acute Meckel's diverticulitis and differentiate it from acute appendicitis. A 60-year-old patient was admitted to our hospital with the diagnosis of acute appendicitis. Abdominal ultrasound was performed and a blind ending, liquid-filled segment of small bowel in the right lower quadrant of the abdomen found. This segment was not compressible, no peristalsis was evident, nor was there any anatomical association with the cecum. Locally we found free fluid and hints of inflamed mesenteric fatty tissue. A perforated Meckel's diverticulum was diagnosed and confirmed intraoperatively. The major ultrasonographic difference between an inflamed Meckel's diverticulum and acute appendicitis is its anatomical location. In contrast to the appendix there is no association with the cecum. A diameter of up to 40 mm and a well-defined wall of small bowel with 3 definite layers visible by ultrasound may help to distinguish between a Meckel's diverticulum and the appendix.

Purpose There is a wide spectrum of tumor responsiveness of rectal adenocarcinomas to preoperative chemoradiotherapy ranging from complete response to complete resistance. This study aimed to investigate whether parallel gene expression profiling of the primary tumor can contribute to stratification of patients into groups of responders or nonresponders. Patients and Methods Pretherapeutic biopsies from 30 locally advanced rectal carcinomas were analyzed for gene expression signatures using microarrays. All patients were participants of a phase III clinical trial (CAO/ARO/AlO-94, German Rectal Cancer Trial) and were randomized to receive a preoperative combined-modality therapy including fluorouracil and radiation. Class comparison was used to identify a set of genes that were differentially expressed between responders and nonresponders as measured by T level downsizing and histopathologic tumor regression grading. Results In an initial set of 23 patients, responders and nonresponclers showed significantly different expression levels for 54 genes (P < .001). The ability to predict response to therapy using gene expression profiles was rigorously evaluated using leave-one-out cross-validation. Tumor behavior was correctly predicted in 83% of patients (P = .02). Sensitivity (correct prediction of response) was 78%, and specificity (correct prediction of nonresponse) was 86%, with a positive and negative predictive value of 78% and 86%, respectively. Conclusion Our results suggest that pretherapeutic gene expression profiling may assist in response prediction of rectal adenocarcinomas to preoperative chemoradiotherapy. The implementation of gene expression profiles for treatment stratification and clinical management of cancer patients requires validation in large, independent studies, which are now warranted.

Introduction: Endorectal ultrasound (EU) is the most important examination for pretherapeutic stratification of primary rectal tumors. Preoperative histology and endosonography determine the therapeutic strategy by using the criteria of depth of infiltration (uT) and lymph node status (uN). Methods: The effectiveness of endoluminal ultrasound in the preoperative differentiation between locally restricted tumors (adenomas and "low-risk" carcinomas, uT0/1, G1-2) and advanced rectal carcinomas (uT3) was assessed in a retrospective study of 284 patients. In the examination period (UZ) from 3/94 to 12/97 (UZ I) 104 patients (group 1) were examined with a 7-MHz endoprobe, and from 1/98 to 12/99 (UZ II), 116 (group 2) with a 10-MHz endoprobe. Additionally, in 64 patients (group 3) with an advanced uT3/4 or uN + tumor we compared the accuracy of ultrasound with computed tomography (CT). In this group 32 patients were restaged by EU and CT after preoperative chemoradiation. The results of preoperative endorectal ultrasound were correlated with the postoperative histological data. Results: Concerning the whole period (UZ I and II) we achieved a total hit rate of 83.6% for adenomas and "low-risk" carcinomas (uT0/1, G1/2) by EU (79.8 % in UZ I, 87.1 % in UZ II). For advanced rectal carcinoma (2 uT3) we found a total accuracy of 87.3% (82.7 % in UZ I, 91.4% in UZ II). In 62 cases endosonographic lymph node status was correlated with postoperative histology during UZ II, with a hit rate of 64.5%. In group 3 (n = 64), in 32 patients without preoperative chemoradiation we found an accuracy for depth infiltration of 93% (EU) and 82 % (CT). Concerning lymph node status there was a correlation of 57% (EU) and 64% (CT). After preoperative chemoradiation (n = 32) we found an accuracy of 91 % (EU) and 73% (CT) for depth infiltration - for lymph node status 70% (EU) and 82% (CT). Conclusions: High accuracy in endoluminal ultrasound leads to a secure and differentiated stratification of therapy in primary rectal tumors. The hit rate concerning depth of infiltration is higher for EU than for CT both before and after chemoradiation, but not regarding lymph node status.

We report on the case of a 38-year-old male patient with a huge extramural gastrointestinal stromal tumour (GIST) of the stomach, located in the left upper and middle abdominal cavity that was diagnosed on the basis of a spontaneous rupture and consecutive haemoperitoneum. The lesion was resected completely in an emergency operation. The tumour was classified as a high-risk lesion for aggressive biological behaviour and with regard to tumour rupture with perforation of the serosa, an adjuvant systemic therapy was indicated.

Purpose: The prognosis of patients with colorectal cancer is largely determined by tumor stage. In this respect, colorectal cancers with lymph node metastases indicate a worse prognosis versus lymph node-negative tumors. Accordingly, there is considerable clinical interest in understanding the genetic mechanisms underlying metastasis formation. Furthermore, sensitive and specific biomarkers are needed to predict the metastatic phenotype at the time of diagnosis. Experimental Design: Fifty colorectal cancers with or without lymph node metastases were assessed for genomic imbalances by comparative genomic hybridization. Particular interest was focused on whether specific chromosomal alterations exist in primary tumors that might be indicative and specific for the metastatic phenotype. Results: The analysis revealed that lymph node-positive colorectal cancers show a higher degree of chromosomal instability than lymph node-negative cancers (average number of chromosomal copy alterations, 9.8 versus 7.5). Chromosomal alterations commonly described in colorectal cancers such as gain of 20q or loss of 18q21 were not different. However, the gain of chromosomal region 8q23-24 was seen in the vast majority of lymph node-positive cancers, whereas it was rather rare in lymph node-negative carcinomas (P = 0.0016). Conclusions: These data suggest that genes located at 8q23-24 might favor the development of lymphatic metastases in colorectal cancers. Additionally, the gain of this region could be used to predict the metastatic potential of primary colorectal cancers.

Background: The tyrosine kinase inhibitor imatinib has been introduced into the treatment of gastrointestinal stromal tumors (GIST). Here we report our results of prolonged treatment in comparison to a similar group of GIST patients who had died before imatinib became available. Methods: Fourteen patients with recurrent or metastatic GIST were treated with imatinib. Clinical data and tumor samples of ten patients from the pre-imatinib era were available for comparison. Comparative genomic hybridisation (CGH) was performed on tumors to identify changes that may predict response to treatment. Results: Fourteen patients were treated, mean treatment time 22.3 months (1 nonresponse, 2 progression after initial response, 2 stable diseases, 8 partial responses, 1 complete response). Adverse side effects were mild in general. Survival was higher in the treated group (41.1 months vs. 34.8 months in the historical group). Eleven treated patients are alive. CGH analysis showed comparable numbers of chromosomal aberations in both groups. Conclusion: Prolonged treatment with imatinib is safe and effective in patients with recurrent or metastatic GIST.

Gastrointestinal stromal tumors (GIST) are the most frequent soft tissue tumors of the gastrointestinal tract. The demonstration of KIT expression (CD117) defined GIST as a distinct tumor entity. Despite many improvements in the medical therapy, complete tumor resection remains the standard treatment for resectable GIST and is the precondition for cure. Data concerning the role of laparoscopic surgery are sparse, but small gastric GIST (< 5 cm) could be a good indication for laparoscopic procedures. In principle laparoscopic GIST resections should be performed only by interdisciplinary teams of surgeons and gastroenterologists experienced in laparoscopy, endoscopy, and oncology.

Background. The biocompatibility of meshes in hernia surgery seems to be influenced markedly by the amount of the selected material and its structure. Fibroblasts play a major key role during the process of mesh incorporation. This study was performed to investigate differences in cell morphology and proliferation of human fibroblasts cultured on different polypropylene meshes. Methods. In the present in vitro study the cellular response of human fibroblasts was investigated by scanning electron microscopy (SEM), comparing three different polypropylene meshes: a newly constructed low-weight and microporous mesh (NK1), a low-weight and macroporous mesh with absorbable polyglactin filaments (Vypro), and a heavy-weight and microporous mesh (BiomeshP1). Human fibroblasts (1,5.105 cells) were incubated with the meshes (each 12 mm(2)) for 6 hours, 5 days, 2,4,6, and 12 weeks. Computer-assisted morphometry of the fibroblast/mesh surface ratio served to reflect the biological cell response. Results. The Vypro mesh showed the significantly highest fibroblast density during the first 6 weeks, but cell growth was nearly exclusively limited to the polyglactin filaments. At 3 months, after reabsorption of the polyglactin, the fibroblast-coated polypropylene mesh surface was only 50% compared to NK1 and BiomeshP1. The morphologic aspect of the fibroblasts on the BiomeshP1 mesh was much more degenerative and unphysiological, compared to NK1 and Vypro, with isolated, single cells instead of a broad, connective growth. The BiomeshP1 showed a significantly higher fibroblast proliferation around the nodes of the mesh compared to the straight filaments. On the NK1 mesh fibroblasts exclusively proliferated on the filaments but not on the pressed mesh surface. Conclusions. The polymer surface and structure appears to be of major importance for the biocompatibility of meshes: human fibroblasts preferably grow on low-weight meshes, thin filaments, and mesh nodes. Heavyweight meshes induce degenerative cell reactions. Polyglactin seems to further improve cell proliferation whereas a pressed mesh surface without pores hinders fibroblast growth.