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Annals of Surgery | 2007

Postpancreatectomy Hemorrhage: Diagnosis and Treatment: An Analysis in 1669 Consecutive Pancreatic Resections

Emre F. Yekebas; Lars Wolfram; Guellue Cataldegirmen; Christian R. Habermann; Dean Bogoevski; Alexandra M. Koenig; Jussuf T. Kaifi; Paulus G. Schurr; Michael Bubenheim; Claus Nolte-Ernsting; Gerhard Adam; Jakob R. Izbicki

Background:To analyze clinical courses and outcome of postpancreatectomy hemorrhage (PPH) after major pancreatic surgery. Summary Background Data:Although PPH is the most life-threatening complication following pancreatic surgery, standardized rules for its management do not exist. Methods:Between 1992 and 2006, 1524 patients operated on for pancreatic diseases were included in a prospective database. A risk stratification of PPH according to the following parameters was performed: severity of PPH classified as mild (drop of hemoglobin concentration <3 g/dL) or severe (>3 g/dL), time of PPH occurrence (early, first to fifth postoperative day; late, after sixth day), coincident pancreatic fistula, intraluminal or extraluminal bleeding manifestation, and presence of “complex” vascular pathologies (erosions, pseudoaneurysms). Success rates of interventional endoscopy and angiography in preventing relaparotomy were analyzed as well as PPH-related overall outcome. Results:Prevalence of PPH was 5.7% (n = 87) distributed almost equally among patients suffering from malignancies, borderline tumors, and focal pancreatitis (n = 47) and from chronic pancreatitis (n = 40). PPH-related overall mortality of 16% (n = 14) was closely associated with 1) the occurrence of pancreatic fistula (13 of 14); 2) vascular pathologies, ie, erosions and pseudoaneurysms (12 of 14); 3) delayed PPH occurrence (14 of 14); and 4) underlying disease with lethal PPH found only in patients with soft texture of the pancreatic remnant, while no patient with chronic pancreatitis died. Conversely, primary severity of PPH (mild vs. severe) and the kind of index operation (Whipple resection, pylorus-preserving partial pancreaticoduodenectomy, organ-preserving procedures) had no influence on outcome of PPH. Endoscopy was successful in 3 from 15 patients (20%), who had intraluminal PPH within the first or second postoperative day. “True,” early extraluminal PPH had uniformly to be treated by relaparotomy. Seventeen patients had “false,” early extraluminal PPH due to primarily intraluminal bleeding site from the pancreaticoenteric anastomosis with secondary disruption of the anastomosis. From 43 patients subjected to angiography, 25 underwent interventional coiling with a success rate of 80% (n = 20). Overall, relaparotomy was performed in 60 patients among whom 33 underwent surgery as first-line treatment, while 27 were relaparotomied as rescue treatment after failure of interventional endoscopy or radiology. Conclusion:Prognosis of PPH depends mainly on the presence of preceding pancreatic fistula. Decision making as to the indication for nonsurgical interventions should consider time of onset, presence of pancreatic fistula, vascular pathologies, and the underlying disease.


Annals of Surgery | 2008

Is it time for a new TNM classification in esophageal carcinoma

Dean Bogoevski; Florian Onken; Alexandra M. Koenig; Jussuf T. Kaifi; Paulus G. Schurr; Guido Sauter; Jakob R. Izbicki; Emre F. Yekebas

Purpose:To investigate the importance of lymph node yield (LNY) and the ratio of afflicted lymph nodes in esophageal carcinoma patients. Patients and Methods:Between 1992 and 2004, 368 patients with esophageal carcinoma underwent surgery. Esophagectomy with curative intent was performed in 255 patients. Subtotal esophagectomy was performed either by thoracoabdominal (104 patients, 40.8%) or by transhiatal approach (151 patients, 59.2%). Results:According to the LNY, patients were grouped into 3 groups. Twenty-six patients had ≤5, 96 had 6 to 18, and 113 had ≥19 dissected lymph nodes. In patients with nodal involvement (pN1), no significant overall survival differences were identified when stratifying subgroups according to the LNY. However, LNY had striking prognostic relevance in pN0 patients. The median overall survival was 23 (≤5 LN), 36 (6–18 LN), and 88 months (≥19). Even for patients with tripled LNY than the proposed minimum by the International Union Against Cancer (UICC) (18 LN), the rate of patients with detected lymph node metastases was only 46%, compared with 61% for patients with a LNY of ≥19 (P = 0.002). In pN1 patients classified according to the ratio of afflicted lymph nodes, median overall survival was 27 months in patients with a ratio <11%, compared with 15 and 13 months in patients with a ratio of 11% to 33% and >33%, respectively (P < 0.001). Multivariate Cox regression modeling identified ratio as the strongest independent prognostic factor for overall survival in pN1 and the LNY in pN0 patients. Conclusions:The minimal regional LNY of 6 lymph nodes as recommended by the UICC for esophageal carcinoma is far too low to appropriately stage the disease. The LNY and the ratio should be reflected in the next version of the UICC classification.


Modern Pathology | 2012

Heterogeneity of ERBB2 amplification in adenocarcinoma, squamous cell carcinoma and large cell undifferentiated carcinoma of the lung

Tobias Grob; Ivonne Kannengiesser; Maria C. Tsourlakis; Djordje Atanackovic; Alexandra M. Koenig; Yogesh K. Vashist; Hans Klose; Andreas Marx; Susan Koops; Ronald Simon; Jakob R. Izbicki; Carsten Bokemeyer; Guido Sauter; Waldemar Wilczak

The HER2 protein, encoded by the ERBB2 gene, is a molecular target for the treatment of breast and gastric cancer by monoclonal antibodies or tyrosine kinase inhibitors. While intratumoral heterogeneity of ERBB2 amplification is rare in breast cancer it is reported to be frequent in bladder and colorectal cancer. To address the potential heterogeneity of the HER2 status in adenocarcinomas, squamous cell carcinomas and large cell undifferentiated carcinomas of the lung, 590 tumors were analyzed for HER2 overexpression and ERBB2 amplification using FDA-approved reagents for immunohistochemistry and fluorescence in-situ hybridization (FISH). Moderate and strong immunostaining (2+, 3+) was seen in 10% of the tumors. ERBB2 amplification was found in 17 (3%) lung cancer patients including 10 cases (2%) with high-level amplification forming gene clusters. ERBB2 amplification was significantly related to histologic subtype and tumor grade, resulting in 12% ERBB2 amplified tumors in the subgroup of high-grade adenocarcinomas. Heterogeneity was analyzed in all highly amplified tumors. For this purpose, all available tumor tissue blocks from these patients were evaluated. Heterogeneity of ERBB2 amplification was found in 4 of 10 tumors as assessed by FISH. These included two tumors with a mixture of low-level and high-level amplification and two tumors with non-amplified tumor areas next to regions with high-level ERBB2 amplification. High-level ERBB2 amplification occurs in a small fraction of lung cancers with a strong propensity to high-grade adenocarcinomas. Heterogeneity of amplification may limit the utility of anti-HER2 therapy in some of these tumors. Further attempts to assess the utility of HER2-targeting therapy in homogeneously amplified lung cancers appear to be justified.


Surgery | 2010

Extended central pancreatic resection as an alternative for extended left or extended right resection for appropriate pancreatic neoplasms

Guellue Cataldegirmen; Claus Schneider; Dean Bogoevski; Alexandra M. Koenig; Jussuf T. Kaifi; Maximilian Bockhorn; Lena Deutsch; Yogesh K. Vashist; Jakob R. Izbicki; Emre F. Yekebas

BACKGROUND Whether patients with focal pancreatic lesions of benign or borderline pathology should be treated by extended central pancreatectomy rather than by extended classic resectional procedures, such as extended right and left resections, is controversial. METHODS Between 1992 and 2007, 105 patients underwent operation for focal pancreatic lesions of borderline or benign neuroendocrine neoplasms, cystadenoma, intraductal papillary mucinous neoplasia (IPMN), and secondary metastasis. In all, 35 patients were subjected to extended central pancreatectomy, whereas the remaining 70 patients were treated by an extended classic right resection or an extended classic left resection. Groups were matched according to age, sex, and histopathology. RESULTS No peri-operative mortality occurred after extended central pancreatectomy and extended classic left resection (n = 35, each). Two (6%) patients died after extended classic right resection. Overall, in-hospital morbidity was 26% after extended central pancreatectomy, 43% after extended classic right resection, and 37% after extended classic left resection. After a median follow-up of 48 months, a local recurrence rate of 17% after extended central pancreatectomy was similar to the corresponding rates of 9% after extended classic left resection and 14% after extended classic right resection. Endocrine and exocrine impairment was less pronounced after extended central pancreatectomy (6% and 9%) than after extended classic left resection (34% and 29%) and extended classic right resection (28% and 24%; P < .05). CONCLUSION Extended central pancreatectomy for appropriate pancreatic neoplasms is associated with less peri-operative morbidity and mortality than after extended classic left and extended classic right resection. Long-term local recurrence after extended central pancreatectomy is similar to the recurrence rates after extended classic right and classic left resection. Our results suggest that appropriately selected patients will benefit from extended central pancreatectomy because of the maintenance of endocrine and exocrine function.


Lung Cancer | 2013

Frequent intratumoral heterogeneity of EGFR gene copy gain in non-small cell lung cancer

Tobias Grob; Tobias Hoenig; Till Sebastian Clauditz; Djordje Atanackovic; Alexandra M. Koenig; Yogesh K. Vashist; Hans Klose; Ronald Simon; Klaus Pantel; Jakob R. Izbicki; Carsten Bokemeyer; Guido Sauter; Waldemar Wilczak

Next to EGFR mutation, EGFR gene copy number evaluated by fluorescence in situ hybridization (FISH) emerged as a potential predictive marker for sensitivity to EGFR tyrosine kinase inhibitors, although controversial data exist. As the diagnostic accuracy of predictive biomarkers can be substantially limited by regional differences within tumors, heterogeneity of EGFR gene copy gain in NSCLC was assessed in this study. For this purpose, a novel tissue microarray (TMA) based analysis platform was developed. TMAs were constructed containing 8 different tissue cylinders from 144 primary NSCLCs. From 62 of these patients additional nodal metastases were sampled. EGFR gene copy number and EGFR expression was analyzed by FISH and immunohistochemistry according to the suggested guidelines. 13 (9.0%) of the 144 evaluated tumors showed EGFR amplification and 37 (25.7%) tumors high polysomy in at least one tumor area. In 7 (53.8%) of 13 amplified cases the analysis of different tumor areas revealed subclones without EGFR gene copy gain next to subclones with amplification. All of the 36 evaluable tumors with high polysomy showed heterogeneity of EGFR gene copy number with areas negative for gene copy gain within the individual tumors. Heterogeneity of EGFR gene copy gain in lung cancer challenges the concept of using small biopsies for the analysis of EGFR FISH status. EGFR gene copy number is highly heterogeneous within individual NSCLCs and this finding might well be a reason for the controversial clinical data existing regarding responsiveness to anti-EGFR therapy.


Journal of Surgical Oncology | 2011

Heme oxygenase-1 germ line GTn promoter polymorphism is an independent prognosticator of tumor recurrence and survival in pancreatic cancer

Yogesh K. Vashist; Guentac Uzungolu; Asad Kutup; Florian Gebauer; Alexandra M. Koenig; Lena Deutsch; Oliver Zehler; Philipp Busch; Viacheslav Kalinin; Jakob R. Izbicki; Emre F. Yekebas

Heme oxygenase‐1 (HO‐1) correlates with aggressive tumor behavior and chemotherapy resistance in pancreatic cancer (PC). We evaluated the prognostic value of the basal transcription controlling germ line GTn repeat polymorphism (GTn) in the promoter region of the HO‐1 gene in PC.


The Annals of Thoracic Surgery | 2012

An Attempt at Validation of the Seventh Edition of the Classification by the International Union Against Cancer for Esophageal Carcinoma

Matthias Reeh; Michael F. Nentwich; Katharina von Loga; Julia Schade; Faik G. Uzunoglu; Alexandra M. Koenig; Maximilian Bockhorn; Thomas Rösch; Jakob R. Izbicki; Dean Bogoevski

BACKGROUND The aim of our study was to investigate the ability of the Seventh edition of the classification by the International Union Against Cancer (UICC) to identify patients at higher risk and to predict the overall survival in patients with esophageal carcinoma. METHODS Demographic and clinical data of 605 patients, who underwent esophagectomy for esophageal carcinoma between 1992 and 2009, were analyzed. Tumor stage and grade were classified according to the sixth and seventh editions of the UICC classification. RESULTS Tumor depth (T), lymph node affection (N), and metastasis (M) status according to the seventh edition of the UICC classification showed significant differences in survival of each single status. Kaplan-Meier analysis of overall survival by the seventh edition of the UICC classification showed poor discrimination between stages Ib and IIa (p=0.098), stages IIIa and IIIb (p=0.672), and stages IIIc and IV (p=0.799). Further, the estimated median survival time between stages IIa and IIb was discordant. CONCLUSIONS The seventh edition of the UICC TNM classification cannot satisfactorily distinguish among different risk groups of patients with resected esophageal carcinoma. The new subgroups do not unify the different TNM stages with similar survival. We strongly propose that the next revision of the UICC classification should reduce the stages to groups with similar survival, without defining complex subgroups.


Annals of Surgery | 2012

Ultrasonic dissection versus conventional dissection techniques in pancreatic surgery: a randomized multicentre study

Faik G. Uzunoglu; Anne Stehr; Judith Alexandra Fink; Eik Vettorazzi; Alexandra M. Koenig; Karim A. Gawad; Yogesh K. Vashist; Asad Kutup; Oliver Mann; Francesca Gavazzi; Alessandro Zerbi; Claudio Bassi; Christos Dervenis; Marco Montorsi; Maximilian Bockhorn; Jakob R. Izbicki

Objective:This prospective randomized multicenter trial was performed to assess the potential benefits of ultrasonic energy dissection compared with conventional dissection techniques in pancreatic surgery. Background:Surgical procedures for tumors of the pancreatic head involve time-consuming manual dissection. The primary hypothesis was that use of ultrasonic tissue and vessel dissection would lead to substantial saving in operative time during pancreatic resection. Methods:Patients eligible for pancreaticoduodenectomy (PD) or pylorus-preserving PD (PPPD) were randomized to group A (dissection with ultrasonic device) or group B (conventional dissection) from March 2009 to May 2011. The primary endpoint was overall duration of operation time. Secondary endpoints were time to end of resection phase, intraoperative blood loss, number of transfused units of blood, and postoperative morbidity. Results:Analysis of primary and secondary endpoints included 101 patients, who received either PD or PPPD. Demographical characteristics and clinical parameters were similar in both groups. The use of an ultrasonic dissection device did not significantly reduce overall operation time (median 316 minutes in group A and 319 minutes in group B, P = 0.95) and did not significantly increase the costs of surgery. Analysis of secondary endpoints revealed no difference in postoperative course. Conclusions:Tissue dissection and vessel closure using an ultrasonic device is equivalent to dissection with conventional techniques in pancreatic surgery.


Journal of Medical Case Reports | 2009

Perivascular epitheloid cell tumour (PEComa) of the retroperitoneum – a rare tumor with uncertain malignant behaviour: a case report

Alexandra M. Koenig; Alexander Quaas; Thorsten Ries; Emre F. Yekebas; Karim A. Gawad; Yogesh K. Vashist; Christoph Burdelski; Oliver Mann; Jakob R. Izbicki; Andreas Erbersdobler

IntroductionPerivascular epitheloid cell tumours are rare mesenchymal neoplasms characterized by a proliferation of perivascular cells with an epitheloid phenotype and expression of myomelanocytic markers.Case presentationHere we present the case of a cystic perivascular epitheloid cell tumour of the retroperitoneum associated with multifocal lung lesions. A 27-year-old woman underwent laparotomy to remove a 10 × 6 × 4 cm sized retroperitoneal mass. The resected specimen was subjected to frozen and permanent histological sections with conventional and immunohistochemical stains, including antibodies against HMB45. The tumour displayed the typical morphological and immunohistochemical features of a perivascular epitheloid cell tumour. Focal necrosis and a proliferative index of 10% suggested a malignant potential. Moreover, postoperative computed tomography scans demonstrated multiple lung lesions, which were radiologically interpreted as being most likely compatible with lymphangioleiomyomatosis.ConclusionSince lymphangioleiomyomatosis, an otherwise benign condition, belongs to the family of perivascular epitheloid cell tumours, it cannot be excluded that the lung lesions in this case in fact represent metastases from the retroperitoneal perivascular epitheloid cell tumour rather than independent neoplasms. More experience with this new and unusual tumour entity is clearly needed in order to define reliable criteria for benign or malignant behaviour.


Histopathology | 2009

Haeme oxygenase‐1 promoter polymorphism is an independent prognostic marker of gastrointestinal stromal tumour

Yogesh K. Vashist; Guentac Uzunoglu; Guelle Cataldegirmen; Viacheslar Kalinin; Paulus G. Schurr; Alexandra M. Koenig; Sabrina Thieltges; Oliver Zehler; Claus Schneider; J. R. Izbicki; Emre F. Yekebas

Aims:  Gastrointestinal stromal tumours (GISTs) display genetic alterations on chromosome 22. GTn repeat (GTn) length polymorphism in the promoter of haeme oxygenase‐1 gene (HMOX‐1) is located on chromosome 22 and associated with malignant growth. The aim was to investigate the role of HMOX‐1 promoter polymorphism in GIST patients.

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