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Dive into the research topics where Gerd Leder is active.

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Featured researches published by Gerd Leder.


Ejso | 1997

Palliative and adjuvant regional chemotherapy in pancreatic cancer

Karl H. Link; Frank Gansauge; Johannes Görich; Gerd Leder; Norbert Rilinger; Hans G. Beger

To improve the dismal prognosis of patients (pts) with pancreatic cancer we treated 32 patients with non-resectable (UICC III, 17 pts; UICC IV, 15 pts--group 1) and 20 patients with resected (UICC I, 1 pt; UICC II, 3 pts; UICC III, 16 pts--group 2) pancreatic cancer with palliative (group I) and adjuvant post-operative (group II) coeliac axis intra-arterial cyclic infusions (CAI). CAI consisted of mitoxantrone 10 mg/m2 on day 1, folinic acid 170 mg/m2 and 5-FU 600 mg/m2 during days 2-4, and cis-platinum 60 mg/m2 on day 5 for up to 11 (group I) or six (group II) cycles. In a total of 211 cycles toxicities at the level of WHO III occurred in 0-6% and of WHO IV in 0%. The median survival times, compared with institutional historical controls (treated vs controls), were 12 vs 4.8 months in UICC III (P < 0.006) and 4 vs 2.9 months in UICC IV (P < 0.05) group I pts, and 21 vs 9.3 months in group II (P < 0.0003). Hepatic disease progression appeared to be suppressed with CAI, which also appears to be effective for palliative and adjuvant treatment in non-resectable and resected pancreatic cancer.


Seminars in Surgical Oncology | 1998

In vitro concentration response studies and in vitro phase II tests as the experimental basis for regional chemotherapeutic protocols.

K. H. Link; Gerd Leder; J. Pillasch; Urwe Butzer; Ludger Staib; Marko Kornmann; Uwe B. Brückner; Hans G. Beger

The theoretical pharmacologic benefit of regional vs. systemic chemotherapy is defined and the concentration response behavior of cytostatic drugs and their optimal exposure times are described with human cancer cell lines (HT29, NMG64/84) and fresh human tumor cell suspensions in the human tumor colony assay (HTCA). The theoretical pharmacological advantages are 5.8 to 6 for adriamycin (ADM), 8 for cisplatinum (CDDP), 6.3 for epidoxorubicin (EPI), 22 to 58 for 5-fluorouracil (5FU), 4.6 for mitomycin C (MMC), and 6.3 for mitoxantrone (NOV). The drugs differed in their cytotoxic potency in vitro and thus also potential efficacy for regional chemotherapy; however, all but 5-fluorodeoxyuridine (5FUDR) exerted cytotoxicity dependent on exposure time and concentration. On average, elevation of the test concentrations by 1 lg doubled responses in fresh human tumor cell suspensions. From these results and clinical considerations, optimal times were defined for the regional chemotherapy strategies of hepatic artery infusion, intraperitoneal instillation, and chemoembolisation as performed at our institution.


Cancer | 2001

Regional chemotherapy of nonresectable colorectal liver metastases with mitoxantrone, 5‐fluorouracil, folinic acid, and mitomycin C may prolong survival

Karl H. Link; Ellen Sunelaitis; Marko Kornmann; Miriam Schatz; Frank Gansauge; Gerd Leder; Andrea Formentini; Ludger Staib; J. Pillasch; Hans G. Beger

Regional chemotherapy of isolated, nonresectable colorectal liver metastases (CRLMs) by hepatic artery infusion (HAI) has the advantages of high response rates and the possibility of downstaging and resection of CRLMs. 5‐Fluorodeoxyuridine (5‐FUDR) has been the drug studied in most Phase II and III trials. The meta‐analysis of the Phase III trials comparing HAI with systemic or supportive therapy confirmed an advantage for response and even survival for HAI. Hepatic artery infusion with 5‐FUDR, however, is hepatotoxic, inducing sclerosing cholangitis (SC). The authors have introduced 5‐fluorouracil (5‐FU) with folinic acid for HAI and found equal effectivity but no SC when compared with HAI with 5‐FUDR. Now, they report a new combination chemotherapy protocol based on HAI with 5‐FU with FA and on in vitro Phase II studies suggesting mitoxantrone and mitomycin C as active drugs for HAI in CRLM.


Langenbeck's Archives of Surgery | 1999

REGIONAL CHEMOTHERAPY OF NON-RESECTABLE LIVER METASTASES FROM COLORECTAL CANCER : LITERATURE AND INSTITUTIONAL REVIEW

Karl H. Link; Marko Kornmann; Andrea Formentini; Gerd Leder; E. Sunelaitis; M. Schatz; J. Preßmar; H. G. Beger

Abstract Background: Cure is possible by resecting colorectal isolated liver metastases. In non-resectable isolated colorectal liver metastases (CRLM), regional chemotherapy has been advocated to optimize the disease control in the liver in order to improve the results of the alternative, systemic chemotherapy. The drugs are delivered by means of hepatic artery infusion (HAI) via ports or pumps; pharmacological modifications of the hepatic arterial blood-flow-like HAI with starch microspheres or stop-flow and perfusion techniques were applied to improve HAI. Methods: We reviewed the literature and report our progress, up to May 1999, in analyzing the validity of HAI for CRLM therapy. Results: In the majority of phase-II and -III trials, the response rates to HAI were significantly higher than those from systemic chemotherapy, and local disease control could be achieved even when HAI was used second line to systemic chemotherapy. The meta-analysis of randomized trials comparing HAI with either systemic chemotherapy (five trials) or, optionally, either 5-fluorouracil (FU) or symptomatic treatment (two trials) showed a significant advantage of HAI in response (41% vs 14%, P<10–10) and median survival time (15 months vs 11 months, P<0.0009). The active anabolite of 5-FU, 5-fluordeoxyuridine (5-FUDR), the drug of choice for HAI in those trials, may cause severe hepatotoxicity. To avoid this toxicity, we developed a HAI protocol using mitoxantrone, 5-FU plus folinic acid (FA) and mitomycin C (MFFM). The response rates of HAI with 5-FU plus FA or MFFM were 45% and 66%, the interim median survival times 19.8 months and 27.4 months. 5-Year survivors were observed in all our protocols. Since no severe hepatotoxicity occurred, 9 of 74 patients were resected after response to HAI with 5-FU plus FA or MFFM, without surgical mortality and with survival times from 2+ months to 58+ months. Conclusion: The high response rates, the long survival times, the possibility of achieving 5-year-survival either by HAI alone or by resection after down staging with HAI all sum up to the evidence that HAI could be the primary choice of treatment for CRLM. Phase-III trials are conducted to compare the protocols with optimal regional versus systemic chemotherapy.


Clinical Cancer Research | 2004

Down-Regulation of BRCA1 in Chronic Pancreatitis and Sporadic Pancreatic Adenocarcinoma

Carmela Beger; Marco Ramadani; Stephan Meyer; Gerd Leder; Martin Krüger; Karl Welte; Frank Gansauge; Hans G. Beger

Purpose: BRCA1 and BRCA2 are considered to be breast cancer susceptibility genes that may also contribute to pancreatic cancer development because family studies revealed mutation carriers to have an increased risk of developing pancreatic cancer. However, as demonstrated for breast and ovarian cancer, inactivation of BRCA in sporadic diseases is based on alteration in gene expression or functional alteration. Experimental Design: To study a potential correlation of BRCA1 and BRCA2 to chronic pancreatitis and development of sporadic pancreatic adenocarcinoma, we have analyzed the expression of these genes by quantitative PCR and performed immunohistochemical analyses in normal pancreatic tissues, chronic pancreatitis, and pancreatic cancer specimens. Results: BRCA1 expression was down-regulated in chronic alcoholic pancreatitis, in particular on the RNA level. Furthermore, our data indicate suppressed BRCA1 expression in pancreatic cancer on both the RNA and protein levels. Quantitative analysis of BRCA1 protein expression demonstrated regular staining in 50% of tumor specimens tested and reduced staining in 50% of tumor specimens tested. Correlation with the clinical outcome revealed a significantly better 1-year overall survival for patients with BRCA1-regular as compared with BRCA1-reduced or BRCA1-absent tumors. In contrast, no substantial differences in BRCA2 expression were found in chronic pancreatitis and pancreatic cancer samples. Conclusions: Our data demonstrate alteration of BRCA1 expression in chronic pancreatitis and sporadic pancreatic adenocarcinoma. We, for the first time, provide evidence for a role of BRCA1 in pancreatic carcinogenesis of noninherited tumors and for clinical outcome.


International Journal of Colorectal Disease | 2009

Interleukin-13 exerts autocrine growth-promoting effects on human pancreatic cancer, and its expression correlates with a propensity for lymph node metastases.

Andrea Formentini; Olga Prokopchuk; Joern Sträter; Joerg Kleeff; Lukasz Filip Grochola; Gerd Leder; Doris Henne-Bruns; Murray Korc; Marko Kornmann

Background and aimsInterleukin-13 (IL-13) is an anti-inflammatory cytokine produced in cells of hematopoetic origin. It is not known whether pancreatic cancer cells produce IL-13 or whether IL-13 can modulate pancreatic cancer cell growth and influence the frequency of lymph node metastases.Materials and methodsCell growth and signaling were analyzed by cell counting, colorimetric proliferation assays, fluorescent-activated cell sorting, and in vitro kinase activity assays. IL-13 expression and secretion were determined by Northern blot analysis and enzyme-linked immunosorbent assay, respectively. Localization of IL-13 and its transmembrane receptor (IL-4R) in primary pancreatic ductal adenocarcinoma (PDAC) was characterized by immunohistochemistry.ResultsIL-13 enhanced the growth of ASPC-1, CAPAN-1, and COLO-357 cells. This was associated with enhanced p44/42 mitogen-activated protein kinase (MAPK) phoshorylation. In contrast to p44/42 MAPK, phosphatidylinositol 3-kinase activity was also induced in IL-13-unresponsive MIA PaCa-2, PANC-1, and T3M4 cells. All cells expressed and secreted IL-13. Neutralizing IL-13 antibodies inhibited the growth of ASPC-1 and CAPAN-1 cells. Immunohistochemical analysis of resected primary ductal adenocarcinoma specimens revealed high levels of IL-13 in 30 of 70 cases and its transmembrane receptor (IL-4R) in 28 of 70 cases, respectively. Fifteen of 16 specimens (94%) exhibiting high IL-13 and IL-4R coexpression had lymph node metastases, while only 30 of the remaining 54 samples (56%) had positive lymph nodes (p = 0.0134).ConclusionIL-13 can act as an autocrine growth factor in PDAC. Endogenous expression of IL-13 in conjunction with IL-4R in the cancer cells seems to facilitate lymph node metastasis.


Deutsches Arzteblatt International | 2008

Pancreatic Cancer – Low Survival Rates

Hans G. Beger; Bettina Rau; Frank Gansauge; Gerd Leder; Michael Schwarz; Bertram Poch

INTRODUCTION Cancers of the pancreas are identified in 11 800 to 13 500 patients each year in Germany. Epidemiological studies prove smoking and chronic alcohol consumption as causes of about 30% of pancreatic cancers. METHODS Selective literature review. RESULTS Only patients within TNM stage I and II have after oncologic tumor extirpation a chance for long term survival. Controlled prospective clinical trials demonstrated adjuvant chemotherapy yielding an additional significant survival benefit. The 3- and 5-year-survival after R0-resection and adjuvant chemotherapy are about 30% and below 15% respectively. Using the criteria of observed 5-year-survival less than 2% of all pancreatic cancer patients are alive. After R0-resection the median survival time is between 17 and 28 months, after R1/2-resection between 8 and 22 months. DISCUSSION Pancreatic cancer is even today for more than 95% of the patients incurable. Strategies to prevent pancreatic cancer are intended to stop smoking and chronic alcohol consumption and early surgical extirpation of cystic neoplastic lesions. For patients with established pancreatic cancer risk a follow-up protocol is discussed.


Langenbeck's Archives of Surgery | 1998

Resection and radiochemotherapy of pancreatic cancer – the future?

Karl H. Link; Andrea Formentini; Gerd Leder; G. Fortnagel; N. Sartori; M. Schatz; H. G. Beger

Background: To improve the surgical outcome after resection of pancreatic adenocarcinomas, multimodal treatment concepts need to be applied and improved. The controversies among those being pro and contra adjuvant treatment need an up-to-date review of the indications and results achievable with various treatment modalities. Patients/Methods: The literature regarding the indications and results of adjuvant/neoadjuvant therapies in pancreatic cancer was reviewed to provide a solid base for current recommendations and future developments. The biology of the disease in the spontaneous course, after surgery and during/after various palliative and adjuvant/neoadjuvant treatment modalities was focussed on, to characterise the disease for an optimally targeted treatment in conjunction with surgical removal of the tumour. The results of systemic and regional chemotherapy and radiotherapy, either alone or in combination, before, during and after surgery were critically analysed with respect to the oncological possibilities and pitfalls of each treatment method. Results: In two randomised trials, one testing postoperative radiochemotherapy (GITSG), and one postoperative chemotherapy, the adjuvant treatment achieved a significant prolongation of the median survival time. The 5-year and 10-year survival rates were improved in the GITSG study. The EORTC-GITCCG trial could not confirm the benefit of adjuvant radiochemotherapy. This study had a different design than the GITSG trial. Several historical control studies supported the beneficial effect of postoperative radiochemotherapy. In three historical control trials using regional chemotherapy, one with intraoperative radiotherapy , the survival times were improved compared with surgery alone. Intraoperative or postoperative radiotherapy as single modalities might reduce local relapses, but a survival advantage is still debated. Preoperative neoadjuvant radiochemotherapy has several advantages (downstaging, devitalising margins and lymph node metastases, compatibility of treatment vs. postoperative radiochemotherapy), and does not seem to increase the postoperative morbidity. Several trials have confirmed the feasibility of this concept, but no survival advantage has yet been proven. Systemic and regional chemotherapy is able to downstage primarily nonresectable pancreatic cancers. Conclusions: Postoperative adjuvant radiochemotherapy with up-to-date protocols can be recommended for routine treatment, if the surgeon or the patient desires to improve the usually remote prognosis after surgery alone. For those being indecisive or against adjuvant therapy, the participation in trials, e.g. the ESPAC 1 and 2 studies, is strongly recommended. Regarding our own positive experience with adjuvant regional chemotherapy and in view of the postresectional progression pattern, we currently favour adjuvant radiochemotherapy, with the chemotherapy delivered regionally via the celiac axis. This concept will be tested against surgery alone in the ESPAC 2 trial. Neoadjuvant therapies have a great potential, but should be conducted within studies, such as pre-, intra-, or postoperative radiotherapy.


Chirurg | 2008

Rare cause of recurring necrotising pancreatitis

Gerd Leder; Andrea Formentini; M. Hoffmann; Doris Henne-Bruns

BACKGROUND Necrotising pancreatitis may develop as a consequence of pancreatic duct obstruction by stones, tumors or in the presence of a pancreas divisum. Alcohol and nicotine are regarded as risk factors for the disease becoming chronic. PATIENT AND COURSE OF THE DISEASE A 63-year-old female patient with suspected cystadenocarcinoma of the pancreas tail, which was resolved as a pancreatic pseudocyst, was treated for recurrent pancreatitis for 2 years. A tumor in the pancreas head was only detected on a follow-up CT after resection of a complicating liver abscess. In retrospect, progressive pancreatic duct anomalies were visible on previous scans. Partial duodenopancreatectomy confirmed the presence of a pancreas head carcinoma. CONCLUSION Continuous critical re-evaluation of all potential causes of pancreatitis including rare conditions, such as a tumor, is required particularly if pancreatitis recurs over a long period. Re-evaluation of studies over time and of findings apart from the actual main focus of the complication, in this case pancreatitis of the pancreas tail, may help to detect the underlying disease instead of just treating the consequences.


Chirurg | 2008

Seltene Ursache einer rezidivierenden, nekrotisierenden Pankreatitis@@@Rare cause of recurring necrotising pancreatitis

Gerd Leder; Andrea Formentini; M. Hoffmann; Doris Henne-Bruns

BACKGROUND Necrotising pancreatitis may develop as a consequence of pancreatic duct obstruction by stones, tumors or in the presence of a pancreas divisum. Alcohol and nicotine are regarded as risk factors for the disease becoming chronic. PATIENT AND COURSE OF THE DISEASE A 63-year-old female patient with suspected cystadenocarcinoma of the pancreas tail, which was resolved as a pancreatic pseudocyst, was treated for recurrent pancreatitis for 2 years. A tumor in the pancreas head was only detected on a follow-up CT after resection of a complicating liver abscess. In retrospect, progressive pancreatic duct anomalies were visible on previous scans. Partial duodenopancreatectomy confirmed the presence of a pancreas head carcinoma. CONCLUSION Continuous critical re-evaluation of all potential causes of pancreatitis including rare conditions, such as a tumor, is required particularly if pancreatitis recurs over a long period. Re-evaluation of studies over time and of findings apart from the actual main focus of the complication, in this case pancreatitis of the pancreas tail, may help to detect the underlying disease instead of just treating the consequences.

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