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J Klempnauer

Publications and source records attributed to J Klempnauer.

At least 91 records · Page 5Linked to original sources
PubMed2000

Cytogenetic aberrations in primary and recurrent fibrolamellar hepatocellular carcinoma detected by comparative genomic hybridization.

Fibrolamellar hepatocellular carcinoma (FLC) is a rare entity of hepatocellular carcinoma (HCC) not yet analyzed cytogenetically. By using comparative genomic hybridization (CGH), we looked for chromosome changes in 2 primary FLCs and a recurrent FLC with and without metastases. CGH revealed an amplification of 1q in 1 primary FLC. The other primary FLC and a metastasis revealed no changes. The recurrent FLC showed 18 aberrations, including 1q+, 2p+, 3p+, 3q+, 4p+, 4q+, 5p+, 5q+, 6q+, 8p+, 8q+, 9q+, 12p+, 12q+, 18p+, 18q+, Xp+, and Xq+. In 2 metastases, 9 and 10 aberrations were seen, including 1q+, 3p-, 3q-, 4q+, 5p+, 5q+, 8q+, 10p+, 10q+, Xp+, and Xq+. In 9 cases of other entities of HCC, a mean of 10.2 aberrations per case were detectable affecting 1q (7 cases), 4q (5), 5q (4), 6q (5), 8p (5), 8q (5), 9p (4), 9q (5), 16q (4), 17p (5), and 17q (4). Chromosomes 2p, 2q, 3p, 3q, 4p, 5p, 6p, 7p, 7q, 10q, 11p, 11q, 12p, 12q, 13q, 14q, 16p, 18p, 18q, 20p, 20q, and 21q were altered in up to 3 samples. Our findings indicate striking differences in the number of chromosomal imbalances in primary FLC and recurrent FLC, whereas imbalances seen in the recurrent FLC and the other entities of HCC were similar in number and chromosomes involved. It may be speculated that these aberrations represent secondary events based on a genetic instability and do not mirror the primary alterations in these carcinomas.

Adult↗
PubMed2000

Data warehouse and data mining in a surgical clinic.

Hospitals and clinics have taken advantage of information systems to streamline many clinical and administrative processes. However, the potential of health care information technology as a source of data for clinical and administrative decision support has not been fully explored. In response to pressure for timely information, many hospitals are developing clinical data warehouses. This paper attempts to identify problem areas in the process of developing a data warehouse to support data mining in surgery. Based on the experience from a data warehouse in surgery several solutions are discussed.

Databases, Bibliographic↗
PubMed1999

Solid-pseudopapillary tumor of the pancreas--a rare and frequently misdiagnosed neoplasm.

INTRODUCTION: We describe a young woman with an unusual pancreatic tumor. FINDINGS AND DISCUSSION: Intraoperatively, a smoothly demarcated and encapsulated tumor was exposed. It was large (5 cmx4 cm) and of solid consistency, with a small stalk attached to the uncinate process. The tumor was partially surrounded by the pancreatic head. The macroscopic appearance suggested a benign tumor. Frozen sections revealed a benign pancreatic tumor, most likely of endocrine nature. Based on these findings, tumor enucleation was performed. The patient recovered rapidly from the intervention and was discharged from hospital after 2 weeks. One year after surgical treatment, the patient is without recurrence. The final diagnosis of the tumor was a solid pseudo-papillary tumor.

Adult↗
PubMed1999

Invasive differentiated thyroid carcinoma: tracheal resection and reconstruction procedures in the hands of the endocrine surgeon.

BACKGROUND: Although differentiated carcinoma of the thyroid gland is a relatively benign tumor, up to 20% of patients are endangered by potentially fatal complications resulting from infiltrating tumor growth into the upper aerodigestive tract. METHODS: This study included 33 patients who underwent 34 tracheal or laryngotracheal procedures for invasive differentiated thyroid carcinoma under the direction of a single surgeon (G.F.W.S.). From 1990 to 1994, radical tumor extirpation was performed by "window" resection, and from 1995 to 1998, radical surgery consisted of either circumferential sleeve resection or laryngotracheal "step" resection--a novel method of reconstruction in cases of unilateral tumor infiltration into the larynx and trachea. Resection was limited to laminar ablation in 17 cases. The mean follow-up of 16 patients who survived was 42.5 months (range, 2 months to 8.9 years). RESULTS: Procedures resulting in primary end-to-end anastomosis of the upper airways were associated with lower perioperative morbidity and improved recurrence-free survival when compared with "window" resections with muscle flap reconstruction. In cases of superficial tracheal tumor infiltration, laminar ablations were sufficient for local tumor control. CONCLUSIONS: Radical eradication of differentiated thyroid carcinoma infiltrating the upper airways followed by radioiodine application should be considered the treatment of choice. Laryngotracheal "step" resection allows tumor extirpation with preservation of neural and muscular structures of the larynx.

Adult↗
PubMed1999

Peripheral hepatojejunostomy as palliative treatment for irresectable malignant tumors of the liver hilum.

OBJECTIVE: To evaluate the concept of surgical decompression of the biliary tree by peripheral hepatojejunostomy for palliative treatment of jaundice in patients with irresectable malignant tumors of the liver hilum. SUMMARY BACKGROUND DATA: Jaundice, pruritus, and recurrent cholangitis are major clinical complications in patients with obstructive cholestasis resulting from malignant tumors of the liver hilum. Methods for palliative treatment include endoscopic stenting, percutaneous transhepatic drainage, and surgical decompression. The palliative treatment of choice should be safe, effective, and comfortable for the patient. METHODS: In a retrospective study, surgical technique, perioperative complications, and efficacy of treatment were analyzed for 56 patients who had received a peripheral hepatojejunostomy between 1982 and 1997. Laparotomy in all of these patients had been performed as an attempt for curative resection. RESULTS: Hepatojejunostomy was exclusively palliative in 50 patients and was used for bridging to resection or transplantation in 7. Anastomosis was bilateral in 36 patients and unilateral in 20. The 1-month mortality in the study group was 9%; median survival was 6 months. In patients surviving >1 month, a marked and persistent decrease in cholestasis was achieved in 87%, although complete return to normal was rare. Among the patients with a marked decrease in cholestasis, 72% had no or only mild clinical symptoms such as fever or jaundice. CONCLUSIONS: Peripheral hepatojejunostomy is a feasible and reasonably effective palliative treatment for patients with irresectable tumors of the liver hilum. In patients undergoing exploratory laparotomy for attempted curative resection, this procedure frequently leads to persistent-although rarely complete-decompression of the biliary tree. In a few cases it may also be used for bridging to transplantation or liver resection after relief of cholestasis.

Adult↗
PubMed1999

CMV in kidney transplantation: a single center experience over 22 years.

Analysis of a historic renal transplant population for risks of developing CMV disease demonstrated a low mortality (0.2%) and morbidity. In our population of 1,959 patients, 411 (21%) developed subclinical CMV infection and 220 (11%) had CMV disease which was severe in 41 (2%). Important factors for infection were baseline immunosuppression, indicating that triple therapy with the proliferation inhibitors, azathioprine and MMF, had significantly higher infection numbers in comparison to dual, CsA-based immunosuppression. The cumulative dose of steroids correlated strongly with an increased number of CMV infections and disease, as did the addition of ALG/ATG or OKT3 for either steroid-resistant rejections or induction therapy. While CMV serology had an impact on infection in cases of seropositive donors to seronegative recipients, seropositive patients, in general, demonstrated increased infection rates most likely due to reactivation of the virus. Prophylaxis had no impact on the incidence of infection but reduced the severity.

Adult↗
PubMed1998

[Pancreas transplantation with bladder and intestinal drainage technique with systemic-venous and initial experiences with portal venous drainage. Which technique can be recommended today?].

The experience worldwide with pancreas transplantation includes more than 9000 cases. In the most popular patient group (simultaneous pancreas-kidney transplantation, SPK) the graft-function rate at 1 year now reaches more than 80%. More than 90% of all pancreas transplants were performed using the bladder-drainage technique (BD) with systemic venous anastomosis. Late problems with the BD require enteric conversion in 10-20% in the long term. In the present study we report the results of 40 SPK using the BD (n = 20) and enteric drainage (ED) techniques (n = 20). After 3 months, the patients pancreas and kidney survival rates in the BD group were 100, 95 and 100% and in the ED group 100, 100 and 100%, respectively. No anastomosis leakage occurred in either group. In two cases of the ED group the pancreas grafts were drained portal venously via the superior mesenteric vein without surgical complications. With growing experience, excellent SPK results can be reached with both the BD and ED techniques.

Adult↗
PubMed1998

Ovarian-like stroma in an invasive mucinous cystadenocarcinoma of the pancreas positive for inhibin. A hint concerning its possible histogenesis.

A female patient with a mucinous cystadenocarcinoma originating from a mucinous cystadenoma of the pancreas is presented. The cystic tumour was diagnosed 3 years before and was treated with interventional external and internal surgical drainage before radical resection was accomplished by left hemipancreatectomy. Histology showed simultaneous occurrence of mildly dysplastic and invasive malignant epithelium. Immunohistology revealed inhibin-positive cells in the ovarianlike stroma of the tumour. The demonstration of ovarian-like stroma positive for inhibin suggests that this could be a hamartoma with dispersed sex-cord stroma, which would explain the predominance of the female gender in mucinous cystic tumours of the pancreas.

Adult↗
PubMed1998

Expression of proliferation associated antigens and detection of numerical chromosome aberrations in primary human liver tumours: relevance to tumour characteristics and prognosis.

AIMS: To assess cell proliferation and the presence of numerical chromosome aberrations involving chromosomes 1 and 8 in benign and malignant liver tumours. METHODS: Cell proliferation was studied immunohistochemically in paraffin wax embedded material from 62 primary liver tumours (20 hepatocellular carcinomas, 16 cholangiocellular carcinomas, 15 liver cell adenomas, 11 focal nodular hyperplasias), and the results were compared with histological characteristics and clinical data. Copy numbers of chromosomes 1 and 8 were assessed by interphase fluorescence in situ hybridisation (FISH) with satellite probes in fresh tumour material. RESULTS: The expression of proliferation associated antigen Ki67, using the monoclonal antibody MIB-1, and proliferating cell nuclear antigen (PCNA), using the antibody PC10, was found to be significantly higher in malignant versus benign liver tumours. Neither Ki67 nor PCNA expression were independent prognostic parameters. However, there was a tendency for a worse outcome (survival < 12 months) for patients with a high MIB-1 labelling index (> 20%) compared with patients having the same tumour stage and a low MIB-1 index. Aneusomy for chromosomes 1 and 8 was demonstrated by FISH in malignant tumours (six of seven hepatocellular carcinomas, four of five cholangiocellular carcinomas) but not in benign tumours (none of nine) or non-neoplastic liver (none of nine). CONCLUSION: Both the determination of the proliferating cell fraction and FISH analysis are useful for distinguishing hepatocellular carcinoma from liver cell adenoma or focal nodular hyperplasia; high fractions of proliferating cells are predictive of an early relapse.

Antigens, Neoplasm↗
PubMed1998

Carcinoma of the ampulla of vater: determinants of long-term survival in 94 resected patients.

This retrospective study details 94 patients after surgical resection of carcinoma of the ampulla of Vater to determine prognostic factors. The tumour was limited to the ampulla of Vater in 32%, invaded the duodenal wall in 34%, infiltrated 2 cm or less into the pancreas in 22%, and invaded more than 2 cm into the pancreas and/or other adjacent structures in 11%. Curative resection was accomplished in 97% of cases. After exclusion of perioperative deaths the 1-, 5- and 10-year survival rates were 79.6%, 38.2%, and 31.6%, respectively with a median survival of 3.68 years. 26 patients survived more than five and 15 patients more than ten years. In an univariate analysis advanced tumour size, poor tumour grading, lymph node metastases and advanced UICC stage significantly decreased survival. Comparison of short and long survivors confirmed tumour size, lymph node status and UICC stage as significant prognostic factors. In a multivariate analysis (Cox model), only tumour size was a statistically independent predictor of prognosis. The survival probability increased with each year a patient survived after resection. When a patient had already survived five years after resection, the probability to survive another five years was 83%. Careful clinicopathologic staging is important for the prognosis after resection.

Adult↗
PubMed1998

[Diagnostic and therapeutic strategies in hepatocellular adenoma].

While liver hemangioma and focal nodular hyperplasia are not considered an indication for surgery in asymptomatic patients resection has been recommended for hepatocellular adenoma because of the risk of rupture and malignant transformation. Problems arise from differential diagnosis and the appropriate surgical radicality including the indication for liver transplantation. This retrospective analysis deals with 58 patients who underwent surgery for hepatocellular adenoma: resection of different extension: n = 54, liver transplantation n = 4. In 39.6% of the patients the tumor was an incidental finding. In 62.0% of the character of the lesion was unclear prior to surgery. Tumor rupture and bleeding occurred in 17.2%, malignant transformation in 6.9%. Surgical morbidity was 27.6%, mortality 5.2% with the transplant patients alive for 1.5, 7, 9 and 10 years. Two and five years after resection 2 patients developed hepatocellular carcinoma in the liver remnant. The results confirm the indication for surgery in hepatocellular adenoma. Diagnostic approach for solid liver tumors without serum increase of tumor markers should rule out FNH and hemangioma. In all other patients surgery should be considered whenever possible with the radicality of malignant disease. Liver transplantation can be discussed even in asymptomatic patients with multiple adenoma.

Adenoma, Liver Cell↗
PubMed1997

Endothelin-1 potently stimulates chloride secretion and inhibits Na(+)-glucose absorption in human intestine in vitro.

1. Serosally added synthetic endothelin-1 (ET-1) increased short-circuit current (Isc) across isolated muscle-stripped human colonic mucosa in vitro. Bumetanide inhibited Isc responses, indicating that ET-1 stimulates electrogenic Cl- secretion. 2. In isolated human jejunal mucosa, ET-1 exhibited a concentration-dependent dual action. At low concentrations it induced rapid increases in Isc and these were inhibited by bumetanide. At a higher concentration (0.1 microM), ET-1 provoked a drastic and progressive decrease in Isc below the baseline value. 3. Pretreatment with phlorizin or omission of glucose from the Krebs-Ringer solution at the apical (luminal) side of the jejunal mucosa prevented the decreases in Isc evoked by ET-1, suggesting that the peptide inhibits the glucose-coupled electrogenic Na+ absorption. Indeed, flux experiments with D-[14C]glucose demonstrated that ET-1 decreases jejunal glucose absorption by approximately 80% within 30 min. 4. Electron microprobe analyses of cryosections of human jejunum showed that ET-1 (0.1 microM) evokes a significant decrease in intracellular Na+ concentrations of villus (not crypt) epithelial cells, suggesting that the peptide attenuates apical Na(+)-glucose entry by reducing the activity of the Na(+)-glucose cotransporter, SGLT1. 5. In the presence of tetrodotoxin (TTX), ET-1-induced Cl- secretion was significantly reduced, in both human jejunal and colonic mucosa. However, the inhibitory effect on jejunal Na(+)-glucose absorption was not affected by TTX. 6. ET-1 increases electrogenic Cl- secretion across human intestinal mucosa in vitro. This effect is mediated in part via the activation of enteric nerves. Responses of the human jejunal mucosa to high ET-1 concentrations exhibit a second component, namely the rapid inhibition of electrogenic Na(+)-glucose absorption, which might be mediated by an inhibition of the transport activity of SGLT1. This effect is independent from neuronal mediators. Our results suggest different cellular action sites for ET-1 in human small and large intestine.

Absorption↗
PubMed1997

What constitutes long-term survival after surgery for hilar cholangiocarcinoma?

BACKGROUND: Hilar cholangiocarcinomas are rarely considered to be resectable and specific data regarding long-term survival are not available. METHODS: A retrospective single center experience from 1971 and 1995 details long-term survival among 339 patients who underwent surgery for adenocarcinoma of the hepatic duct bifurcation. Tumor removal was accomplished by resection of the bile duct bifurcation either alone (33 patients), in combination with hepatic resection (77 patients), or combined with hepatic and vascular resection (41 patients). Thirty-two patients underwent total hepatectomy and liver transplantation. In 188 patients the tumor was unresectable and palliative internal or external biliary drainage was established. The resectability rate was 49.2% and rose to 54% after inclusion of liver transplantation. The clinicopathologic features of 32 5-year survivors were compared with patients whose survival was less than 5 years. RESULTS: Thirty-two patients survived longer than 5 years after surgical treatment of hilar cholangiocarcinoma; 22 of these patients (69%) were still alive at last follow-up. Twenty-six long-term survivors had primarily undergone resection; 4 received liver transplants. There was 1 long-term survivor beyond 5 years after both exploratory laparotomy and subsequent percutaneous transhepatic drainage, and palliative hepatojejunostomy. Long-term survival after resection was significantly associated with less advanced tumor stages. Lymph node involvement and residual tumor were the primary prognostic factors both in a multivariate analysis after resection and in the cohort of long-term survivors. Nevertheless, long-term survivors were still at a significant risk to die from tumor recurrence. CONCLUSIONS: Radical resection offers the best possibility of prolonged survival with a good quality of life for patients with hilar cholangiocarcinoma.

Bile Duct Neoplasms↗
PubMed1997

Long-term results after surgery for acute mesenteric ischemia.

BACKGROUND: Acute mesenteric ischemia is associated with high mortality rates, and little is known about the long-term prognosis of patients after initially successful surgical intervention. METHODS: Ninety patients were treated by vascular reconstruction or bowel resection, or both, between 1972 and 1993. The overall mortality was 66%. The outcomes and rehabilitational statuses of those 31 patients who were discharged from the hospital were analyzed retrospectively. Anticoagulation consisted of vitamin K antagonists in patients with venous thrombosis and arterial embolism or inhibition of thrombocyte aggregation in patients with arterial thrombosis and nonocclusive mesenteric ischemia. RESULTS: In 31 patients discharged from the hospital venous thrombosis, arterial embolism, arterial thrombosis, and nonocclusive disease occurred in 19, 5, 5, and 2 patients, respectively. The 2- and 5-year survival rates were 70% and 50% and mainly related to cardiovascular comorbidity and malignant disease. Only one patient died after a recurrent attack of arterial mesenteric thrombosis. Twenty percent of the patients suffered from chronic short bowel syndrome after extensive bowel resection, but none required permanent parenteral nutrition. CONCLUSIONS: Under appropriate anticoagulation there is a remarkably low risk of recurrent mesenteric ischemia. The impaired life expectancy of long-surviving patients is mainly due to cardiovascular comorbidity and malignancies.

Acute Disease↗