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Dive into the research topics where Siegfried Seeber is active.

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Featured researches published by Siegfried Seeber.


Journal of Clinical Oncology | 2005

Chemoradiation With and Without Surgery in Patients With Locally Advanced Squamous Cell Carcinoma of the Esophagus

Michael Stahl; Martin Stuschke; Nils Lehmann; Hans-Joachim Meyer; Martin K. Walz; Siegfried Seeber; Bodo Klump; Wilfried Budach; Reinhard Teichmann; Marcus Schmitt; Gerd Schmitt; Claus Franke; Hansjochen Wilke

PURPOSE Combined chemoradiotherapy with and without surgery are widely accepted alternatives for the curative treatment of patients with locally advanced esophageal cancer. The value of adding surgery to chemotherapy and radiotherapy is unknown. PATIENTS AND METHODS Patients with locally advanced squamous cell carcinoma (SCC) of the esophagus were randomly allocated to either induction chemotherapy followed by chemoradiotherapy (40 Gy) followed by surgery (arm A), or the same induction chemotherapy followed by chemoradiotherapy (at least 65 Gy) without surgery (arm B). Primary outcome was overall survival time. RESULTS The median observation time was 6 years. The analysis of 172 eligible, randomized patients (86 patients per arm) showed overall survival to be equivalent between the two treatment groups (log-rank test for equivalence, P < .05). Local progression-free survival was better in the surgery group (2-year progression-free survival, 64.3%; 95% CI, 52.1% to 76.5%) than in the chemoradiotherapy group (2-year progression-free survival, 40.7%; 95% CI, 28.9% to 52.5%; hazard ratio [HR] for arm B v arm A, 2.1; 95% CI, 1.3 to 3.5; P = .003). Treatment-related mortality was significantly increased in the surgery group than in the chemoradiotherapy group (12.8% v 3.5%, respectively; P = .03). Cox regression analysis revealed clinical tumor response to induction chemotherapy to be the single independent prognostic factor for overall survival (HR, 0.30; 95% CI, 0.19 to 0.47; P < .0001). CONCLUSION Adding surgery to chemoradiotherapy improves local tumor control but does not increase survival of patients with locally advanced esophageal SCC. Tumor response to induction chemotherapy identifies a favorable prognostic group within these high-risk patients, regardless of the treatment group.


Journal of Clinical Oncology | 2005

Phase I Clinical and Pharmacokinetic Study of the Novel Raf Kinase and Vascular Endothelial Growth Factor Receptor Inhibitor BAY 43-9006 in Patients With Advanced Refractory Solid Tumors

Dirk Strumberg; Heike Richly; Ralf A. Hilger; Norbert Schleucher; Sonke Korfee; Mitra Tewes; Markus Faghih; Erich Brendel; Dimitris Voliotis; Claus G. Haase; Brian Schwartz; Ahmad Awada; Rudolf Voigtmann; Max E. Scheulen; Siegfried Seeber

PURPOSE BAY 43-9006 is a novel dual-action Raf kinase and vascular endothelial growth factor receptor inhibitor that inhibits tumor cell proliferation and angiogenesis. This study established the safety and pharmacokinetics of BAY 43-9006 in 69 patients with advanced refractory solid tumors. PATIENTS AND METHODS BAY 43-9006 (50 to 800 mg) was administered once or twice daily on a varying weekly schedule. Pharmacokinetic sampling was performed in all patients; preliminary tumor response was also assessed. The effect of BAY 43-9006 on phorbol myristate acetate-stimulated ERK phosphorylation in peripheral blood lymphocytes was studied using flow cytometry. RESULTS Mild to moderate diarrhea was the most common (55%) treatment-related adverse event. The maximum-tolerated dose was 400 mg bid continuous. Dose-limiting toxicities were grade 3 diarrhea and fatigue at 800 mg bid, and grade 3 skin toxicity at 600 mg bid. BAY 43-9006 pharmacokinetics were highly variable for single and multiple dosing, and toxicity did not appear to be dose dependent. Significant decreases of phorbol myristate acetate-stimulated ERK phosphorylation (P < .01) were identified at doses >/= 200 mg bid continuous. Forty-five patients were assessable for efficacy; one patient had a partial response (hepatocellular carcinoma at 400 mg bid continuous), 25 patients had stable disease, with eight lasting > 6 months and five for >12 months. Eighteen patients had progressive disease, and tumor response could not be evaluated in one patient. CONCLUSION Oral BAY 43-9006 was well tolerated and appeared to provide some clinical benefits. Based on the results of this study, BAY 43-9006 at 400 mg bid continuous is recommended for ongoing and future studies.


Journal of Clinical Oncology | 1998

Preoperative chemotherapy followed by concurrent chemoradiation therapy based on hyperfractionated accelerated radiotherapy and definitive surgery in locally advanced non-small-cell lung cancer: mature results of a phase II trial.

Wilfried Eberhardt; Hansjochen Wilke; Georgios Stamatis; Martin Stuschke; A Harstrick; H. Menker; B Krause; M R Müeller; Michael Stahl; M Flasshove; V Budach; D Greschuchna; N Konietzko; H. Sack; Siegfried Seeber

PURPOSE To evaluate the feasibility and efficacy of an intensive multimodality approach with combination chemotherapy, hyperfractionated accelerated chemoradiotherapy, and definitive surgery in prognostically unfavorable subgroups of locally advanced non-small-cell lung cancer stages IIIA and IIIB (LAD-NSCLC). PATIENTS AND METHODS Following staging, including mediastinoscopy, 94 patients with inoperable LAD-NSCLC were treated preoperatively with chemotherapy (three courses of split-dose cisplatin and etoposide [PE]) followed by concurrent chemoradiotherapy (one course of PE combined with 45 Gy hyperfractionated accelerated radiotherapy). After repeat mediastinoscopy, patients underwent surgery 4 weeks postradiation. RESULTS Of 94 consecutive patients (52 stage IIIA [> or = two lymph node levels involved] and 42 stage IIIB [no pleural effusion, no supraclavicular nodes]), 62 (66%) completed induction and underwent surgery. Complete resection (R0) was achieved in 50 (53% of all patients) and pathologic complete response (PCR) in 24 (26%). After a median follow-up of 43 months, the median survival time was 20 months for IIIA, 18 months for IIIB, and 42 months for R0 patients. Calculated survival rates at 4 years were 31%, 26%, and 46%. Two patients died of sepsis preoperatively and four died postoperatively of pleural empyema (n = 1), stump insufficiency (n = 2), and cardiac failure (n = 1). Other toxicities were acceptable-mainly hematologic during chemotherapy or chemoradiotherapy and esophagitis during chemoradiotherapy. CONCLUSION This intensive multimodality treatment is feasible and demonstrates high efficacy in prognostically unfavorable LAD-NSCLC subgroups with high R0 rates and improved long-term survival compared with historical controls


Journal of Clinical Oncology | 2004

Phase I Study of the Humanized Antiepidermal Growth Factor Receptor Monoclonal Antibody EMD72000 in Patients With Advanced Solid Tumors That Express the Epidermal Growth Factor Receptor

Udo Vanhoefer; Mitra Tewes; Federico Rojo; Olaf Dirsch; Norbert Schleucher; Oliver Rosen; Joachim Tillner; Andreas Kovar; Ada Braun; Tanja Trarbach; Siegfried Seeber; A. Harstrick; José Baselga

PURPOSE To investigate the safety and tolerability and to explore the pharmacokinetic and pharmacodynamic profile of the humanized antiepidermal growth factor receptor monoclonal antibody EMD72000 in patients with solid tumors that express epidermal growth factor receptor (EGFR). PATIENTS AND METHODS This was a phase I dose-escalation trial of EMD72000 in patients with advanced, EGFR-positive, solid malignancies that were not amenable to any established chemotherapy or radiotherapy treatment. EMD72000 was administered weekly without routine premedication until disease progression or unacceptable toxicity. RESULTS Twenty-two patients were treated with EMD72000 at five different dose levels (400 to 2,000 mg/wk). National Cancer Institute common toxicity criteria grade 3 headache and fever occurring after the first infusion were dose limiting at 2,000 mg/wk; thus, the maximum-tolerated dose was 1,600 mg/wk. No other severe side effects, especially no allergic reactions or diarrhea, were observed. Acneiform skin reaction was the most common toxicity, but it was mild, with grade 1 in 11 patients (50%) and grade 2 in three patients (14%). Pharmacokinetic analyses demonstrated a predictable pharmacokinetic profile for EMD72000. Pharmacodynamic studies on serial skin biopsies revealed that EMD72000 effectively abrogated EGFR-mediated cell signaling (eg, reduced phosphorylation of EGFR and mitogen-activated protein kinase), with no alteration in total EGFR protein. Objective responses (23%; 95% CI, 8% to 45%) and disease stabilization (27%; 95% CI, 11% to 50%) were achieved at all dose levels, and responding patients received treatment for up to 18 months without cumulative toxicity. CONCLUSION Treatment with EMD72000 was well tolerated and showed evidence of activity in heavily pretreated patients with EGFR-expressing tumors. EMD72000 at the investigated doses significantly inhibited downstream EGFR-dependent processes.


Journal of Clinical Oncology | 2001

Irinotecan in the Treatment of Colorectal Cancer: Clinical Overview

Udo Vanhoefer; A. Harstrick; Wolf Achterrath; Shousong Cao; Siegfried Seeber; Youcef M. Rustum

PURPOSE AND METHODS For more than three decades, the therapeutic options for patients with advanced colorectal cancer have almost exclusively been based on fluoropyrimidines. With the recognition that topoisomerase-I (TOP-I) is an important therapeutic target in cancer therapy, irinotecan, a semisynthetic TOP-I-interactive camptothecin derivative, has been clinically established in the treatment of colorectal cancer. RESULTS Irinotecan was investigated as second-line chemotherapy after prior treatment with fluorouracil (FU)-based regimens in two large randomized phase III trials comparing irinotecan with either best supportive care or an infusional FU/leucovorin (LV) regimen. The outcomes of these trials established irinotecan as the standard therapy in the second-line treatment of colorectal cancer. The therapeutic value of irinotecan in the first-line treatment of metastatic colorectal cancer was investigated in two large randomized phase III trials comparing the combination of irinotecan and FU/LV with FU/LV alone. Both trials demonstrated significant superior efficacy for the combination of irinotecan and FU/LV in terms of response rate, median time to disease progression, and median survival time. Consequently, the combination of irinotecan and FU/LV has been approved as first-line chemotherapy for patients with metastatic colorectal cancer and constitutes the reference therapy against which other treatment options must be tested in the future. CONCLUSION In this review, the clinical rationale and update of the present clinical status of irinotecan in the treatment of colorectal cancer and future prospects of irinotecan-based combinations are discussed.


Lancet Infectious Diseases | 2002

Update on Kaposi's sarcoma and other HHV8 associated diseases. Part 1: epidemiology, environmental predispositions, clinical manifestations, and therapy

Ulrich R Hengge; Thomas Ruzicka; Stephen K. Tyring; Martin Stuschke; Michael Roggendorf; Robert A. Schwartz; Siegfried Seeber

Kaposis sarcoma (KS) is a mesenchymal tumour involving blood and lymphatic vessels. Only recently has the pathogenesis of this extraordinary neoplasm been elucidated. Viral oncogenesis and cytokine-induced growth together with some state of immunocompromise represent important conditions for this tumour to develop. In 1994, a novel virus was discovered and termed human herpesvirus 8 (HHV8), also known as Kaposis sarcoma-associated herpes virus, which can be found in all types of KS, whether related to HIV or not. In the era of highly active antiretroviral therapy (HAART), the incidence of AIDS-KS has considerably declined, probably due to enhanced immune reconstitution and anti-HHV8-specific immune responses. If HAART is able to prevent spreading of KS, local therapy of KS may become an essential component of patient management. Part 1 of the review covers the epidemiology, environmental predispositions, clinical manifestations, and therapy of KS. Newer treatments such as pegylated liposomal anthracyclines and experimental strategies are discussed. We also present rationales and graduated treatment algorithms for local and systemic therapy in patients with KS to appropriately meet the challenges of this extraordinary neoplasm. Part 2, to be published next month, will summarise recent insights in the pathogenesis of KS and will discuss other HHV8-related diseases such as Castlemans disease and primary effusion lymphoma.


Lancet Infectious Diseases | 2002

Update on Kaposi's sarcoma and other HHV8 associated diseases. Part 2: pathogenesis, Castleman's disease, and pleural effusion lymphoma

Ulrich R. Hengge; Thomas Ruzicka; Stephen K. Tyring; Martin Stuschke; Michael Roggendorf; Robert A. Schwartz; Siegfried Seeber

The pathogenesis of Kaposis sarcoma (KS) is better understood since the identification of the novel human herpesvirus 8 (HHV8), which can be found in all forms of KS. Viral oncogenesis and cytokine-induced growth, as well as some states of immunocompromise, contribute to its development. Several virally encoded genes--eg, bcl-2, interleukin 6, cyclin D, G-protein-coupled receptor, and interferon regulatory factor--provide key functions on cellular proliferation and survival. Growth promotion of KS is further stimulated by various proinflammatory cytokines and growth factors such as tumour necrosis factor a, interleukin 6, basic fibroblast growth factor, and vascular endothelial growth factor, resulting in a hyperplastic polyclonal lesion with predominant spindle cells derived from lymphoid endothelia. HHV8 has recently been discovered to escape HLA-class-I-restricted antigen presentation to cytotoxic T lymphocytes by increasing endocytosis of MHC class I chains from the cell surface, thus enabling latent infection and immune escape in primary and chronic infection. Multicentric Castlemans disease is a rare lymphoproliferative disorder of the plasma cell type, which has been reported in both HIV-seropositive and HIV-seronegative patients, and which frequently contains HHV8 DNA. Pleural effusion lymphoma, or body-cavity-based lymphoma, belongs to the group of non-Hodgkin B-cell lymphomas characterised by pleural, pericardial, or peritoneal lymphomatous effusions in the absence of a solid tumour mass. Pleural effusion lymphoma has an intermediate immunophenotype lacking B or T lymphocyte antigens and also belongs to the diseases associated with HHV8.


Journal of Clinical Oncology | 1999

Prophylactic Cranial Irradiation in Locally Advanced Non–Small-Cell Lung Cancer After Multimodality Treatment: Long-Term Follow-Up and Investigations of Late Neuropsychologic Effects

Martin Stuschke; Wilfried Eberhardt; Christoph Pöttgen; Georgios Stamatis; Hansjochen Wilke; Georg Stüben; F. Stöblen; H. H. Wilhelm; H. Menker; Helmut Teschler; R.-D. Müller; Volker Budach; Siegfried Seeber; H. Sack

PURPOSE Relapse pattern and late toxicities in long-term survivors were analyzed after the introduction of prophylactic cranial irradiation (PCI) into a phase II trial on trimodality treatment of locally advanced (LAD) non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Seventy-five patients with stage IIIA(N2)/IIIB NSCLC were treated with induction chemotherapy, preoperative radiochemotherapy, and surgery. PCI was routinely offered during the second period of study accrual. Patients were given a total radiation dose of 30 Gy (2 Gy per daily fraction) over a 3-week period starting 1 day after the last chemotherapy cycle. RESULTS Introduction of PCI reduced the rate of brain metastases as first site of relapse from 30% to 8% at 4 years (P =.005) and that of overall brain relapse from 54% to 13% (P <.0001). The effect of PCI was also observed in the good-prognosis subgroup of 47 patients who had a partial response or complete response to induction chemotherapy, with a reduction of brain relapse as first failure from 23% to 0% at 4 years (P =.01). Neuropsychologic testing revealed impairments in attention and visual memory in long-term survivors who received PCI as well as in those who did not receive PCI. T2-weighted magnetic resonance imaging revealed white matter abnormalities of higher grades in patients who received PCI than in those who did not. CONCLUSION PCI at a moderate dose reduced brain metastases in LAD-NSCLC to a clinically significant extent, comparable to that in limited-disease small-cell lung cancer. Late toxicity to normal brain was acceptable. This study supports the use of PCI within intense protocols for LAD-NSCLC, particularly in patients with favorable prognostic factors.


Journal of Clinical Oncology | 1997

Thymidylate synthase inhibitors in cancer therapy: direct and indirect inhibitors.

Youcef M. Rustum; A. Harstrick; Shousong Cao; Udo Vanhoefer; Ming-Biao Yin; Hansjochen Wilke; Siegfried Seeber

PURPOSE AND METHODS Although fluoropyrimidines, in particular, fluorouracil (5-FU) and fluorodeoxyuridine (FdUrd), are active alone and in combination with other agents in a variety of human malignancies, therapeutic selectivity, resistance, and efficacy have been a major limitation in cancer therapy. Preclinical and clinical results in advanced and adjuvant colorectal cancers confirmed that the therapeutic efficacy of fluoropyrimidines, with thymidylate synthase (TS) as a primary target, can be improved significantly with leucovorin (LV) modulation. With the recognition that TS is an important therapeutic target, direct and specific inhibitors have been developed and are under intensive preclinical and clinical evaluation, primarily in patients with colorectal cancer, with demonstrable activity. The direct TS inhibitors have been shown to be potent, with a high level of specificity under therapeutic conditions for TS. This includes ZD1694, AG337, and LY231514. To date, although the therapeutic activity of both direct and indirect inhibitors of TS is similar, differences in the magnitude and profile of toxicity have been observed. A phase III comparative evaluation of a direct inhibitor of TS (ZD1694) with an indirect inhibitor (5-FU/LV) has been completed and showed similar activity but reduced toxicity in favor of ZD1694. RESULTS Recognition that greater than 95% of the injected dose of 5-FU is rapidly inactivated by dihydropyrimidine dehydrogenase (DPD) to therapeutically inactive products, but with toxicity to normal tissues, led to the development of inhibitors of this enzyme with the aim to modify the therapeutic index of 5-FU. Several inhibitors in combination with 5-FU are under preclinical and clinical evaluation, including uracil and 5-chloro-2,4-dihydroxy pyridine, as modulators of 5-FU derived from its prodrug tegafur and 5-ethynyluracil as a modulator of 5-FU. CONCLUSION In this review, an update of the present status of direct and indirect inhibitors of TS is discussed, as well as the future prospect for new drugs alone and in combination.


Clinical Immunology and Immunopathology | 1992

Lupus-like autoimmune disease induced by interferon therapy for myeloproliferative disorders

Ursula Wandl; Marianne Nagel-Hiemke; Dieter May; Ernst Kreuzfelder; Otto Kloke; Michael Kranzhoff; Siegfried Seeber; Norbert Niederle

Symptoms of autoimmune disease were evaluated in 125 patients with chronic myelogenous leukemia (CML) and in 12 patients with essential thrombocythemia undergoing treatment with recombinant interferon (IFN)-alpha-2b plus/minus low-dose recombinant IFN-gamma. Twenty-seven of 137 patients (20%) developed rheumatoid symptoms. Furthermore, the incidence of antinuclear antibody (ANA) formation was studied. Elevated ANA titers were found in 5/19 (26%) of CML patients at the time of diagnosis and in 3/18 (17%) of patients treated with hydroxyurea or busulfan. During IFN treatment, 18 of 25 tested patients (72%) had elevated ANA titers. In 15 of these ANA-positive patients, clinical signs of autoimmune disease appeared. All these patients were under long-term IFN treatment and were in remission of disease. In three patients criteria for systemic lupus erythematosus were fulfilled. Severity of side effects had led to the discontinuation of IFN treatment in these patients. The data indicate that IFN-alpha and IFN-gamma can induce ANA associated with autoimmune disease in patients with myeloproliferative disorders.

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A. Harstrick

Hannover Medical School

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Bertram Opalka

University of Duisburg-Essen

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Max E. Scheulen

University of Duisburg-Essen

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Michael Flasshove

University of Duisburg-Essen

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Dirk Strumberg

University of Duisburg-Essen

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Wilfried Eberhardt

University of Duisburg-Essen

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Udo Vanhoefer

Roswell Park Cancer Institute

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