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Dive into the research topics where Dirk Weismann is active.

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Featured researches published by Dirk Weismann.


The New England Journal of Medicine | 2012

Combination chemotherapy in advanced adrenocortical carcinoma

Martin Fassnacht; Massimo Terzolo; Bruno Allolio; Eric Baudin; Harm R. Haak; Alfredo Berruti; Staffan Welin; Carmen Schade-Brittinger; André Lacroix; Barbara Jarzab; Halfdan Sorbye; David J. Torpy; Vinzenz Stepan; David E. Schteingart; Wiebke Arlt; Matthias Kroiss; Sophie Leboulleux; Paola Sperone; Anders Sundin; Ilse Hermsen; Stefanie Hahner; Holger S. Willenberg; Antoine Tabarin; Marcus Quinkler; Martin Schlumberger; Franco Mantero; Dirk Weismann; Felix Beuschlein; Hans Gelderblom; Hanneke Wilmink

BACKGROUND Adrenocortical carcinoma is a rare cancer that has a poor response to cytotoxic treatment. METHODS We randomly assigned 304 patients with advanced adrenocortical carcinoma to receive mitotane plus either a combination of etoposide (100 mg per square meter of body-surface area on days 2 to 4), doxorubicin (40 mg per square meter on day 1), and cisplatin (40 mg per square meter on days 3 and 4) (EDP) every 4 weeks or streptozocin (streptozotocin) (1 g on days 1 to 5 in cycle 1; 2 g on day 1 in subsequent cycles) every 3 weeks. Patients with disease progression received the alternative regimen as second-line therapy. The primary end point was overall survival. RESULTS For first-line therapy, patients in the EDP-mitotane group had a significantly higher response rate than those in the streptozocin-mitotane group (23.2% vs. 9.2%, P<0.001) and longer median progression-free survival (5.0 months vs. 2.1 months; hazard ratio, 0.55; 95% confidence interval [CI], 0.43 to 0.69; P<0.001); there was no significant between-group difference in overall survival (14.8 months and 12.0 months, respectively; hazard ratio, 0.79; 95% CI, 0.61 to 1.02; P=0.07). Among the 185 patients who received the alternative regimen as second-line therapy, the median duration of progression-free survival was 5.6 months in the EDP-mitotane group and 2.2 months in the streptozocin-mitotane group. Patients who did not receive the alternative second-line therapy had better overall survival with first-line EDP plus mitotane (17.1 month) than with streptozocin plus mitotane (4.7 months). Rates of serious adverse events did not differ significantly between treatments. CONCLUSIONS Rates of response and progression-free survival were significantly better with EDP plus mitotane than with streptozocin plus mitotane as first-line therapy, with similar rates of toxic events, although there was no significant difference in overall survival. (Funded by the Swedish Research Council and others; FIRM-ACT ClinicalTrials.gov number, NCT00094497.).


Circulation | 2007

Complementary and incremental mortality risk prediction by cortisol and aldosterone in chronic heart failure

Gülmisal Güder; Johann Bauersachs; Stefan Frantz; Dirk Weismann; Bruno Allolio; Georg Ertl; Christiane E. Angermann; Stefan Störk

Background— In patients with systolic heart failure, high levels of circulating aldosterone are associated with an adverse prognosis, and mineralocorticoid receptor blockade improves survival. The prognostic significance of cortisol that may also bind and activate the mineralocorticoid receptor in chronic heart failure is unknown. Methods and Results— Serum levels of cortisol and aldosterone were quantified in a prospective cohort study of 294 consecutive patients with chronic heart failure [48% were in New York Heart Association functional class III or IV; 58% had systolic heart failure]. During a median follow-up of 803 days (interquartile range, 314 to 1098), 79 patients died (27.3% mortality rate). Cortisol and aldosterone were independent predictors of increased mortality risk in Cox regression analyses adjusted for age, sex, New York Heart Association functional class, C-reactive protein, N-terminal pro-brain natriuretic peptide, sodium, and hypercholesterolemia. The hazard ratio for highest versus lowest tertile of cortisol was 2.72 [95% confidence interval [CI], 1.38 to 5.36; P=0.004], and the hazard ratio for aldosterone was 2.19 (95% CI, 1.23 to 3.93; P=0.008). Patients with both cortisol and aldosterone levels above the respective medians had a 3.4-fold higher mortality risk compared with subjects with both corticosteroids below the median (95% CI, 1.54 to 7.46; P=0.0001). Addition of cortisol and aldosterone levels to the fully adjusted model significantly improved the discriminatory power [increase in Harrell’s C-statistic from 0.80 (95% CI, 0.70 to 0.90) to 0.86 (95% CI, 0.79 to 0.94; P<0.001 for change]. Conclusions— In patients with chronic heart failure, higher serum levels of both cortisol and aldosterone were independent predictors of increased mortality risk that conferred complementary and incremental prognostic value.


European Urology | 2010

Laparoscopic Versus Open Adrenalectomy for Adrenocortical Carcinoma: Surgical and Oncologic Outcome in 152 Patients

David Brix; Bruno Allolio; Wiebke Fenske; Ayman Agha; Henning Dralle; Christian Jurowich; Peter Langer; Thomas Mussack; C. Nies; H. Riedmiller; Martin Spahn; Dirk Weismann; Stefanie Hahner; Martin Fassnacht

BACKGROUND The role of laparoscopic adrenalectomy in the treatment of patients with adrenocortical carcinoma (ACC) is controversial. OBJECTIVE Our aim was to compare oncologic outcome in patients with ACC who underwent either open adrenalectomy (OA) or laparoscopic adrenalectomy (LA) for localised disease. DESIGN, SETTING, AND PARTICIPANTS We conducted a retrospective analysis of 152 patients with stage I-III ACC with a tumour < or =10 cm registered with the German ACC Registry. INTERVENTION Patients were stratified into two groups according to the surgical procedure (LA or OA). For comparison, we used both a matched pairs approach by selecting for each patient from the LA group (n=35) one corresponding patient from the OA group (n=117) and multivariate analysis in all 152 patients. MEASUREMENTS Disease-specific survival was chosen as the predefined primary end point. Secondary end points were recurrence-free survival, frequency of tumour capsule violation and postoperative peritoneal carcinomatosis, and incidence and reasons for conversion from LA to OA. RESULTS AND LIMITATIONS LA and OA did not differ with regard to the primary end point using either the matched pairs approach (hazard ratio [HR] for death: 0.79; 95% confidence interval [CI], 0.36-1.72; p=0.55) or multivariate analysis (HR for death: 0.98; 95% CI, 0.51-1.92; p=0.92). Similarly, adjusted recurrence-free survival was not different between LA and OA (HR: 0.91; 95% CI, 0.56-1.47; p=0.69). Frequency of tumour capsule violation and peritoneal carcinomatosis were comparable between groups. In 12 of 35 patients of the LA group, surgery was converted to open surgery with no impact on the clinical outcome. CONCLUSIONS For localised ACC with a diameter of < or =10 cm, LA by an experienced surgeon is not inferior to OA with regard to oncologic outcome.


Clinical Endocrinology | 2004

Management of adrenocortical carcinoma

Bruno Allolio; Stefanie Hahner; Dirk Weismann; Martin Fassnacht

Adrenocortical carcinoma (ACC) is a rare neoplasm with poor prognosis. Patients present with signs of steroid hormone excess (e.g. Cushings syndrome, virilization) or an abdominal mass. Tumour size at presentation (mean diameter at diagnosis > 10 cm) is the most important indicator of malignancy. In addition, computed tomography (CT) typically demonstrates an inhomogeneous adrenal lesion with irregular margins and variable enhancement of solid components after intravenous contrast media. Magnetic resonance imaging (MRI) is equally effective as CT and is particularly helpful to visualize invasion into large vessels. Complete tumour removal (R0 resection) offers by far the best chance for long‐term survival and therefore surgery is the treatment of choice in stage I–III ACC. Despite tumour resection for cure most patients will eventually develop local recurrence or distant metastases. Thus adjuvant treatment options need to be evaluated in high‐risk patients (e.g. radiation therapy of the tumour bed and/or chemotherapy). In tumour recurrence re‐operation should always be considered. In metastatic disease (stage IV ACC) not amenable to surgery mitotane (o,p′DDD) remains the first‐line therapy. Drug monitoring is needed for effective treatment aiming at concentrations between 14 and 20 mg/l. Patients not responding to mitotane may benefit from cytotoxic chemotherapy (23% partial remissions, 4% complete remissions). Only large prospective multicentre trials comparing different treatment options will allow to make systematic progress in the management of ACC.


The Journal of Clinical Endocrinology and Metabolism | 2010

Improved Survival in Patients with Stage II Adrenocortical Carcinoma Followed Up Prospectively by Specialized Centers

Martin Fassnacht; Sarah Johanssen; Wiebke Fenske; Dirk Weismann; Ayman Agha; Felix Beuschlein; Dagmar Führer; Christian Jurowich; Marcus Quinkler; Stephan Petersenn; Martin Spahn; Stefanie Hahner; Bruno Allolio

CONTEXT Median survival in stage II adrenocortical carcinoma (ACC) differs widely in published series ranging between 23 and more than 60 months. We hypothesized that these results may have been affected by a referral bias because many patients may contact specialized centers only after recurrence. OBJECTIVE The objective of the study was a comparison of outcome in patients with stage II ACC who were followed up prospectively early after surgery and were counseled by a specialized center (prospective group) with patients who registered with the German ACC registry later than 4 months after diagnosis (retrospective group). PATIENTS/METHODS The study was a cohort analysis in 149 adult patients with stage II ACC. RESULTS Patients who were followed up prospectively (n = 30) had a lower recurrence rate and a superior 5-yr survival compared with the 119 patients in the retrospective group (30 vs. 74%, P < 0.01 and 96 vs. 55%, P < 0.05, respectively). In the retrospective group, 67% of the patients had registered only after disease recurrence. In the remaining patients, the recurrence rate was low (21%), and the 5-yr survival was greater than 95%. More patients in the prospective group received adjuvant mitotane (53 vs. 16%, P < 0.001), and adjuvant mitotane was associated with improved survival [hazard risk 0.35 (95% confidence interval 0.13-0.97); P = 0.04]. However, the survival advantage was maintained when only patients without mitotane therapy were analyzed. CONCLUSIONS Patients who are followed up prospectively after surgery for stage II ACC and receive early specialized care have a much better prognosis than previously reported due to a major referral bias in previous series and use of adjuvant mitotane. These findings will impact on the perception of prognosis in newly diagnosed stage II ACC.


Clinical Endocrinology | 2014

Biochemical diagnosis of phaeochromocytoma using plasma-free normetanephrine, metanephrine and methoxytyramine: importance of supine sampling under fasting conditions.

Roland Därr; Christina Pamporaki; Mirko Peitzsch; Konstanze Miehle; Aleksander Prejbisz; Mariola Pęczkowska; Dirk Weismann; Felix Beuschlein; Richard O. Sinnott; Stefan R. Bornstein; Hartmut P. H. Neumann; Andrzej Januszewicz; Jacques W. M. Lenders; Graeme Eisenhofer

To document the influences of blood sampling under supine fasting versus seated nonfasting conditions on diagnosis of phaeochromocytomas and paragangliomas (PPGL) using plasma concentrations of normetanephrine, metanephrine and methoxytyramine.


Clinical Endocrinology | 2006

Intraoperative haemodynamic stability in patients with phaeochromocytoma – minimally invasive vs conventional open surgery

Dirk Weismann; Martin Fassnacht; Fabian Weinberger; Wulf Hamelmann; Saskia Diehl; Kerstin Lorenz; Eckhard Baerlehner; Martin Reincke; Felix Beuschlein; Wolfram T. Knoefel; Christoph Nies; Stefanie Hahner; Bruno Allolio

Objective  There is conflicting evidence, whether or not minimally invasive adrenalectomy (MA) is associated with an increased perioperative cardiovascular instability in phaeochromocytomas compared to conventional open adrenalectomy (CA).


Clinical Endocrinology | 2013

Bariatric surgery for morbid obesity in craniopharyngioma

Dirk Weismann; Theresia Pelka; Gwendolyn Bender; Christian Jurowich; Martin Fassnacht; Andreas Thalheimer; Bruno Allolio

To retrospectively analyse the effectiveness of bariatric surgery for hypothalamic obesity in patients with craniopharyngioma (CP).


European Journal of Endocrinology | 2015

Measurements of plasma metanephrines by immunoassay vs liquid chromatography with tandem mass spectrometry for diagnosis of pheochromocytoma

Dirk Weismann; Mirko Peitzsch; Anna Raida; Aleksander Prejbisz; Maria Gosk; Anna Riester; Holger S. Willenberg; Reiner Klemm; Georg Manz; Timo Deutschbein; Matthias Kroiss; Roland Därr; Martin Bidlingmaier; Andrzej Januszewicz; Graeme Eisenhofer; Martin Fassnacht

BACKGROUND Reports conflict concerning measurements of plasma metanephrines (MNs) for diagnosis of pheochromocytomas/paragangliomas (PPGLs) by immunoassays compared with other methods. We aimed to compare the performance of a commercially available enzyme-linked immunoassay (EIA) kit with liquid chromatography-tandem mass spectrometric (LC-MS/MS) measurements of MNs to diagnose PPGLs. METHODS In a substudy of a prospective, multicenter trial to study the biochemical profiles of monoamine-producing tumors, we included 341 patients (174 males and 167 females) with suspected PPGLs (median age 54 years), of whom 54 had confirmed PPGLs. Plasma MNs were measured by EIA and LC-MS/MS, each in a specialized laboratory. RESULTS Plasma normetanephrine (NMN) and MN were measured 60 and 39% lower by EIA than by LC-MS/MS. Using upper cut-offs stipulated for the EIA, diagnostic sensitivity was only 74.1% at a specificity of 99.3%. In contrast, use of similar cut-offs for MN and overall lower age-adjusted cut-offs for NMN measured by LC-MS/MS returned a diagnostic sensitivity and specificity of 98.1 and 99.7%. Areas under receiver-operating characteristic curves, nevertheless, indicated comparable diagnostic performance of the EIA (0.993) and LC-MS/MS (0.985). Diagnostic sensitivity for the EIA increased to 96.2% with a minimal loss in specificity (95.1%) following use of cut-offs for the EIA adapted to correct for the negative bias. CONCLUSIONS The EIA underestimates plasma MNs and diagnostic sensitivity is poor using commonly stipulated cut-offs, resulting in a high risk for missing patients with PPGLs. Correction of this shortcoming can be achieved by appropriately determined cut-offs resulting in comparable diagnostic performance of EIA and LC-MS/MS assays.


The Journal of Pathology | 2009

Osteopontin stimulates invasion of NCI-h295 cells but is not associated with survival in adrenocortical carcinoma.

Dirk Weismann; Juliane Briese; Joscha Niemann; Matthias Grüneberger; Patrick Adam; Stefanie Hahner; Sarah Johanssen; Wei Liu; Shereen Ezzat; Wolfgang Saeger; Ana-Maria Bamberger; Martin Fassnacht; Heinrich M. Schulte; Sylvia L. Asa; Bruno Allolio; Christoph M. Bamberger

Gene array studies indicated that osteopontin (OPN) mRNA is highly expressed in adrenocortical carcinomas (ACCs). OPN enhances invasiveness, proliferation, and metastasis formation, and is associated with poor survival in some malignant diseases. Integrin αvβ3 has been shown to mediate OPN effects on invasion. In this study, we demonstrated OPN and integrin αvβ3 expression in normal adrenal glands and benign adenomas, with staining seen exclusively in adrenocortical cells as well as even stronger staining in ACC. Western blot analysis confirmed overexpression of OPN in ACC (p < 0.01). With Matrigel invasion assays, we have shown that OPN greatly stimulates the invasiveness of NCI‐h295 cells (>six‐fold increase, p < 0.001). Transfection with integrin αvβ3 further increased invasiveness after OPN stimulation (p < 0.001). This increase was reversed by the addition of an anti‐integrin β3 antibody, indicating a functional relationship of OPN and integrin αvβ3 in ACC. With tissue arrays, we confirmed high OPN expression in 147 ACC samples. However, no association with survival was seen in Kaplan‐Meier analysis including 111 patients with primary tumours graded for OPN staining and follow‐up data available. In conclusion, our in vitro data indicate that OPN and integrin αvβ3 may act as a functional complex facilitating the invasiveness of adrenocortical tumours. This relationship remains of relevance to our understanding of carcinogenesis, but further studies are needed to address the physiological and pathological function of OPN in adrenal tissue. Copyright

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Bruno Allolio

University of Düsseldorf

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Mirko Peitzsch

Dresden University of Technology

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Patrick Adam

University of Tübingen

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Anna Raida

University of Würzburg

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