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Karel Caca

Publications and source records attributed to Karel Caca.

At least 19 recordsLinked to original sources
PubMed2006

Characterization of two phase I metabolites of bendamustine in human liver microsomes and in cancer patients treated with bendamustine hydrochloride.

PURPOSE: The metabolism of bendamustine (BM) hydrochloride, a bifunctional alkylator containing a heterocyclic ring, was investigated in vitro and in vivo for identification of cytochromes P450 (CYP) involved in the formation of two phase I metabolites, structural confirmation of these previously unidentified metabolites and assessment of their cytotoxic effect in relation to the parent compound. METHODS: Potential metabolites of BM were synthesized and structurally characterized by nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry (LC-MS) analysis. In vitro metabolism of BM hydrochloride in human hepatic microsomes was conducted to identify the CYP450 isoenzymes involved in the oxidative metabolism of BM. Samples from cancer patients after treatment with BM hydrochloride and microsomal preparations were analyzed by LC-MS and HPLC with fluorescence detection. The cytotoxic effect of the metabolites was analyzed in several lymphoma cell lines and peripheral blood lymphocytes and compared with that of the parent compound using an MTT assay. RESULTS: LC-MS as well as HPLC with fluorescence detection revealed hydroxylation of the methylene carbon at the C-4 position of the butanoic acid side chain and N-demethylation of the benzimidazole skeleton as the main metabolic pathways in human liver microsomes. Isoform-specific chemical inhibitors and correlation analysis pointed to CYP1A2 as the prominent enzyme in BM oxidation. The rate of formation for both metabolites correlated (r=0.931 and 0.933) with the activity of CYP1A2 and there were no other notable correlations with any of the other CYPs. In addition, both metabolites were identified in plasma, urine, and bile samples from cancer patients under BM hydrochloride therapy as shown by comparison with chromatograms obtained from the authentic reference standards. Cytotoxic activity observed for gamma-hydroxy BM was approximately equivalent to that obtained for the parental compound BM. N-demethyl BM displays five to tenfold less cytotoxic activity than BM. CONCLUSION: The results indicate that CYP1A2-catalyzed N-dealkylation and gamma hydroxylation are the major routes for BM phase I metabolism producing two metabolites less or similarly toxic than the parent compound. In contrast to the metabolic pathways of the structurally related chlorambucil, no beta-oxidation of the butanoic acid side chain leading to enhanced toxicity was detected for BM.

Aged↗
PubMed2006

Expression of c-kit receptor in human cholangiocarcinoma and in vivo treatment with imatinib mesilate in chimeric mice.

AIM: To investigate the c-kit expression in biliary tract cancer cell lines and histological sections from patients with extrahepatic cholangiocarcinoma (CC) and to evaluate the efficacy of in vitro and in vitro treatment with imatinib mesilate. METHODS: The protein expression of c-kit in the human biliary tract cancer cell lines Mz-ChA-2 and EGI-1 and histological sections from 19 patients with extrahepatic CC was assessed by immunoblotting, immunocytochemistry, and immunohistochemistry. The anti-proliferative effect of imatinib mesilate on biliary tract cancer cell lines Mz-ChA-2 and EGI-1 was studied in vitro by automated cell counting. In addition, immunodeficient NMRI mice (Taconic) were subcutaneously injected with 5x10(6) cells of cell lines MzChA-2 and EGI-1. After having reached a tumour volume of 200 mm3, daily treatment was started intraperitoneally with imatinib mesilate at a dose of 50 mg/kg or normal saline (NS). Tumor volume was calculated with a Vernier caliper. After 14 d, mice were sacrificed with tumors excised and tumor mass determined. RESULTS: Immunoblotting revealed presence of c-kit in Mz-ChA-2 and absence in EGI-1 cells. Immunocytochemistry with c-kit antibodies displayed a cytoplasmatic and membraneous localization of receptor protein in Mz-ChA-2 cells and absence of c-kit in EGI-1 cells. c-kit was expressed in 7 of 19 (37%) extrahepatic human CC tissue samples, 2 showed a moderate and 5 a rather weak immunostaining. Imatinib mesilate at a low concentration of 5 micromol/L caused a significant growth inhibition in the c-kit positive cell line Mz-ChA-2 (31%), but not in the c-kit negative cell line EGI-1 (0%) (P<0.05). Imatinib mesilate at an intermediate concentration of 10 micromol/L inhibited cellular growth of both cell lines (51% vs 57%). Imatinib mesilate at a higher concentration of 20 micromol/L seemed to have a general toxic effect on both cell lines. The IC50 values were 9.7 micromol/L and 11 micromol/L, respectively. After 14 d of in vitro treatment with imatinib mesilate, using the chimeric mouse model, c-kit positive Mz-ChA-2 tumors had a significantly reduced volume and mass as compared to NS treatment (P<0.05). In contrast to that, treatment of mice bearing c-kit negative EGI-1 tumors did not result in any change of tumor volume and mass as compared to NS treatment. CONCLUSION: c-kit expression is detectable at a moderate to low protein level in biliary tract cancer. Imatinib mesilate exerts marked effects on tumor growth in vitro and in vitro dependent on the level of c-kit expression.

Animals↗
PubMed2006

Percutaneous transgastric irrigation drainage in combination with endoscopic necrosectomy in necrotizing pancreatitis (with videos).

BACKGROUND: Endoscopic drainage of pancreatic acute and chronic pseudocysts and pancreatic necrosectomy have been shown to be beneficial for critically ill patients, with complete endoscopic resolution rates of around 80%. OBJECTIVE: Our purpose was to describe an improved endoscopic technique used to treat pancreatic necrosis. DESIGN: Case report. SETTING: University hospital. PATIENTS AND INTERVENTIONS: Two patients with large retroperitoneal necroses were treated with percutaneous transgastric retroperitoneal flushing tubes and a percutaneous transgastric jejunal feeding tube by standard percutaneous endoscopic gastrostomy access in addition to endoscopic necrosectomy. RESULTS: Intensive percutaneous transgastric flushing in combination with percutaneous normocaloric enteral nutrition and repeated endoscopic necrosectomy led to excellent outcomes in both patients. LIMITATIONS: Small number of patients. CONCLUSIONS: The "double percutaneous endoscopic gastrostomy" approach for simultaneous transgastric drainage and normocaloric enteral nutrition in severe cases of pancreatic necroses is safe and effective. It could be a promising improvement to endoscopic transgastric treatment options in necrotizing pancreatitis.

Drainage↗
PubMed2006

Endoscopic full-thickness plication for the treatment of gastroesophageal reflux disease: A randomized, sham-controlled trial.

BACKGROUND & AIMS: The aim of this study was to determine the effectiveness of endoscopic full-thickness plication for the treatment of gastroesophageal reflux disease (GERD) in comparison with a sham procedure. METHODS: Patients with symptomatic GERD requiring maintenance proton pump inhibitor (PPI) therapy were entered into a randomized, single-blind, prospective, multicenter trial. Seventy-eight patients were randomly assigned to undergo endoscopic full-thickness restructuring of the gastric cardia with transmural suture. Eighty-one patients underwent a sham procedure. Group assignments were revealed following the 3-month evaluation. The primary end point was > or =50% improvement in GERD health-related quality of life (HRQL) score. Secondary end points included medication use and esophageal acid exposure. RESULTS: By intention-to-treat analysis, at 3 months, the proportion of patients achieving > or =50% improvement in GERD-HRQL score was significantly greater in the active group (56%) compared with the sham group (18.5%; P < .001). Complete cessation of PPI therapy was higher among patients in the active group than in the sham group by intention-to-treat analysis (50% vs 24%; P = .002). The percent reduction in median percent time pH < 4 was significantly improved within the active group versus baseline (7 vs 10, 18%, P < .001) but not in the sham group (10 vs 9, -3%, P = .686). Between-group analysis revealed the active therapy to be superior to the sham in improving median percent time pH < 4 (P = .010). There were no perforations or deaths. CONCLUSIONS: Endoscopic full-thickness plication more effectively reduces GERD symptoms, PPI use, and esophageal acid exposure than a sham procedure.

Endoscopy, Gastrointestinal↗
PubMed2006

Novel targeted approaches to treating biliary tract cancer: the dual epidermal growth factor receptor and ErbB-2 tyrosine kinase inhibitor NVP-AEE788 is more efficient than the epidermal growth factor receptor inhibitors gefitinib and erlotinib.

Aberrant activation of the epidermal growth factor receptor is frequently observed in neoplasia, notably in tumors of epithelial origin. Attempts to treat such tumors with epidermal growth factor receptor antagonists resulted in remarkable success in recent studies. Little is known, however, about the efficacy of this therapy in biliary tract cancer. Protein expression of epidermal growth factor receptor, ErbB-2, and vascular endothelial growth factor receptor-2 was assessed in seven human biliary tract cancer cell lines by immunoblotting. In addition, histological sections from 19 patients with extrahepatic cholangiocarcinoma were analyzed for epidermal growth factor receptor, ErbB-2 and vascular endothelial growth factor receptor-2 expression by immunohistochemistry. Moreover, we sequenced the cDNA products representing the entire epidermal growth factor receptor coding region of the seven cell lines, and searched for genomic epidermal growth factor receptor amplifications and polysomy by fluorescence in-situ hybridization. Cell growth inhibition by gefitinib erlotinib and NVP-AEE788 was studied in vitro by automated cell counting. In addition, the anti-tumoral effect of erlotinib and NVP-AEE788 was studied in a chimeric mouse model. The anti-tumoral drug mechanism in this model was assessed by MIB-1 antibody staining, terminal deoxynucleotidyl transfer-mediated dUTP nick end-labelling assay, von Willebrand factor staining, and immunoblotting for p-p42/44 (p-Erk1/2, p-MAPK) and p-AKT. Immunoblotting revealed expression of epidermal growth factor receptor, ErbB-2, and vascular endothelial growth factor receptor-2 in all biliary tract cancer cell lines. EGFR was detectable in six of 19 (32%) extrahepatic human cholangiocarcinoma tissue samples, ErbB-2 in 16 of 19 (84%), and vascular endothelial growth factor receptor-2 in nine of 19 (47%). Neither epidermal growth factor receptor mutations nor amplifications or polysomy were found in the seven biliary tract cancer cell lines. Gefitinib, erlotinib and NVP-AEE788 caused a significant growth inhibition in vitro; however, there was a significant difference in efficacy (NVP-AEE788>erlotinib>gefitinib). After 14 days of in-vivo treatment, using the chimeric mouse model, tumors had a significantly reduced volume and mass after NVP-AEE788, but not after erlotinib treatment, as compared with placebo. Reduction of proliferation (signalling via the mitogen-activated protein kinase pathway), induction of apoptosis and inhibition of angiogenesis were the main mechanisms of drug action. No significant reduction of anti-apoptotic AKT phosphorylation, however, occurred, which may be a possible counter mechanism of the tumor. Epidermal growth factor receptor, ErbB-2, and vascular endothelial growth factor receptor-2 expression was detectable in biliary tract cancer, and receptor inhibition exerts marked effects on tumor growth in vitro and in vivo, which was strongest for the dual EGFR/ErbB-2 inhibitor NVP-AEE788. Therefore, further clinical evaluation of this new drug for the treatment of biliary tract cancer is recommended.

Animals↗
PubMed2006

Radiochemotherapy followed by gemcitabine and capecitabine in extrahepatic bile duct cancer: a phase I/II trial.

OBJECTIVE: Both radiotherapy and chemotherapy with gemcitabine and capecitabine have efficacy in biliary cancer. Our aim was to determine the toxicity and efficacy of a postoperative regimen combining both treatment modalities in extrahepatic bile duct cancer. METHODS: Patients were eligible after surgery for extrahepatic bile duct adenocarcinoma. Surgery included resection of lymph node positive cancer, incomplete resections and diagnostic laparotomy in unresectable tumors. Patients received a fractionated radiotherapy of 49.6 Gy accompanied by gemcitabine once a week. After a 2-week rest, patients were treated with gemcitabine and capecitabine on a 3-week cycle. The treatment continued for 6 cycles in nonmeasurable disease or until disease progression or intolerable toxicity. RESULTS: There were 18 patients (resection/laparotomy 7/11) enrolled between August 2003 and April 2005. Radiotherapy was completed in all patients and a total of 66 cycles of chemotherapy was applied. Fatigue and nausea were the most common mild adverse events. Grade 3 and 4 toxicity was rare after resection but frequent in unresectable disease and consisted of fatigue, nausea, duodenal ulcer, cachexia, and cholangitis in 1, 2, 2, 4, and 4 patients, respectively. We observed a 50% disease stabilization rate in patients with measurable disease. Median overall survival was 7.9 months in patients with unresectable tumors. Median overall survival in patients after resection has not been reached at a median follow-up of 19.5 months. CONCLUSIONS: Radiochemotherapy using gemcitabine followed by gemcitabine and capecitabine is an active regimen with manageable toxicity after resection of extrahepatic bile duct cancer but has significant toxicity in unresectable disease.

Adenocarcinoma↗
PubMed2006

Surgical and palliative management and outcome in 184 patients with hilar cholangiocarcinoma: palliative photodynamic therapy plus stenting is comparable to r1/r2 resection.

OBJECTIVE: First, to analyze the strategy for 184 patients with hilar cholangiocarcinoma seen and treated at a single interdisciplinary hepatobiliary center during a 10-year period. Second, to compare long-term outcome in patients undergoing surgical or palliative treatment, and third to evaluate the role of photodynamic therapy in this concept. SUMMARY BACKGROUND DATA: Tumor resection is attainable in a minority of patients (<30%). When resection is not possible, radiotherapy and/or chemotherapy have been found to be an ineffective palliative option. Recently, photodynamic therapy (PDT) has been evaluated as a palliative and neoadjuvant modality. METHODS: Treatment and outcome data of 184 patients with hilar cholangiocarcinoma were analyzed prospectively between 1994 and 2004. Sixty patients underwent resection (8 after neoadjuvant PDT); 68 had PDT in addition to stenting and 56 had stenting alone. RESULTS: The 30-day death rate after resection was 8.3%. Major complications occurred in 52%. The overall 1-, 3-, and 5-year survival rates were 69%, 30%, and 22%, respectively. R0, R1, and R2 resection resulted in 5-year survival rates of 27%, 10%, and 0%, respectively. Multivariate analysis identified R0 resection (P < 0.01), grading (P < 0.05), and on the limit to significance venous invasion (P = 0.06) as independent prognostic factors for survival. PDT and stenting resulted in longer median survival (12 vs. 6.4 months, P < 0.01), lower serum bilirubin levels (P < 0.05), and higher Karnofsky performance status (P < 0.01) as compared with stenting alone. Median survival after PDT and stenting, but not after stenting alone, did not differ from that after both R1 and R2 resection. CONCLUSION: Only complete tumor resection, including hepatic resection, enables long-term survival for patients with hilar cholangiocarcinoma. Palliative PDT and subsequent stenting resulted in longer survival than stenting alone and has a similar survival time compared with incomplete R1 and R2 resection. However, these improvements in palliative treatment by PDT will not change the concept of an aggressive resectional approach.

Adult↗
PubMed2005

Chronic pancreatitis with pancreaticolithiasis and pseudocyst in a 5-year-old boy with homozygous SPINK1 mutation.

We report a 5-year-old boy with a 5-month history of symptoms owing to chronic pancreatitis. Abdominal imaging revealed a large pseudocyst in the pancreatic tail and concretions in the main pancreatic duct. Successful endoscopic papillotomy and stent implantation were performed. Genetic testing showed homozygous SPINK1-N34S mutation, which is an established risk factor for chronic pancreatitis.

Child, Preschool↗
PubMed2005

Synthesis and characterization of some new phase II metabolites of the alkylator bendamustine and their identification in human bile, urine, and plasma from patients with cholangiocarcinoma.

The alkylating agent bendamustine is currently in phase III clinical trials for the treatment of hematological malignancies and breast, lung, and gastrointestinal tumors. Renal elimination mainly as the parent compound is thought to be the primary route of excretion. Because polar biliary conjugates were expected metabolites of bendamustine, three cysteine S-conjugates were synthesized, purified by quantitative high-performance liquid chromatography (HPLC), and characterized by NMR spectroscopy and mass spectrometry (MS). HPLC assays with MS, as well as fluorescence detection of bile, urine, and plasma after single-dose intravenous infusion of 140 mg/m(2) bendamustine in five subjects with cholangiocarcinoma, indicated the existence of these phase II metabolites, which were identified as cysteine S-conjugates by comparison with the previously characterized synthetic reference standards. The sum of the three cysteine S-conjugates of bendamustine was determined in human bile and urine to be 95.8 and 26.0%, respectively, expressed as mean percentage of the sum of the parent compound and identified metabolites. The percentage of administered dose recovered in urine as cysteine S-conjugates ranged from 0.9 to 4.1%, whereas the total percentage of the administered dose excreted in urine as the parent drug and seven metabolites ranged from 3.8 to 16.3%. The identification of cysteine S-conjugates provide evidence that a major route of bendamustine metabolism in humans involves conjugation with glutathione. Results indicate the importance of phase II conjugation in the elimination of bendamustine, besides phase I metabolism and hydrolytic degradation, and require further investigation.

Bendamustine Hydrochloride↗
PubMed2005

Caroli's disease: liver resection and liver transplantation. Experience in 33 patients.

BACKGROUND: The aim of this study was to review and discuss our observations on 33 patients who underwent surgical treatment for Caroli's disease (CD), focusing on diagnosis, current surgical management, and long-term outcome. METHODS: Between May 1993 and June 2004, 642 liver resections and 286 liver transplantations in 252 patients were performed in our department of surgery. Thirty-three patients were referred to our center for diagnostic and therapeutic management of CD. Prior surgical interventions for hepatobiliary disorders, current diagnostic and surgical procedures, procedure-specific complications, duration of hospital stay, duration of follow-up, outpatient information, and long-term outcome were reviewed. RESULTS: Fifteen male and 18 female patients were treated in this study. Initial symptoms and signs of the disease noted in our patients included right upper quadrant pain, fever, and jaundice. In 2 of the 33 patients, we noted clinical evidence of cirrhosis followed by histologic confirmation. One patient suffered from variceal bleeding. In 26 patients, diagnoses were established by a combined endoscopic retrograde cholangiopancreatography, ultrasonography, and computed tomographic studies. The disease was localized in 25 and diffuse in 8 patients. Liver resection was carried out in 29 patients. Partial hepatectomies were performed in 27 of these 29 at our institution. Two female patients with the diffuse disease underwent orthotopic liver transplantation. Thirteen of the 31 patients who underwent surgery at our institution had an uneventful postoperative course. Fourteen patients had minor postoperative complications and responded well to medical management. Four patients had major complications that required further surgical treatment. Two patients died of complications related to postoperative hemorrhage and sepsis. Two patients with intrahepatic cholangiocarcinoma died because of primary tumor progress. One patient with cholangiocarcinoma died 1 year after a successful left hepatectomy because of metastatic disease recurrence. The long-term results of the 26 surviving patients were assessed during a mean follow-up of 3.7 years (range, 1-11 years). All 26 patients remained free of biliary symptoms or complications. In 25 patients, surgery including liver transplantation was curative. CONCLUSIONS: Partial hepatectomy for localized CD is potentially curative. In patients with diffuse CD, liver transplantation provides gratifying long-term results.

Adult↗
PubMed2005

Molecularly targeted therapy for gastrointestinal cancer.

Receptor and non-receptor tyrosine kinases (TKs) have emerged as clinically useful drug target molecules for treating gastrointestinal cancer. Imatinib mesilate (STI-571, Gleevec(TM)), an inhibitior of bcr-abl TK, which was primarily designed to treat chronic myeloid leukemia is also an inhibitor of c-kit receptor TK, and is currently the drug of choice for the therapy of metastatic gastrointestinal stromal tumors (GISTs), which frequently express constitutively activated forms of the c-kit-receptor. The epidermal growth factor receptor (EGFR), which is involved in cell proliferation, metastasis and angiogenesis, is another important target. The two main classes of EGFR inhibitors are the TK inhibitors and monoclonal antibodies. Gefitinib (ZD1839, Iressa(TM)) has been on trial for esophageal and colorectal cancer (CRC) and erlotinib (OSI-774, Tarceva(TM)) on trial for esophageal, colorectal, hepatocellular, and biliary carcinoma. In addition, erlotinib has been evaluated in a Phase III study for the treatment of pancreatic cancer. Cetuximab (IMC-C225, Erbitux(TM)), a monoclonal EGFR antibody, has been FDA approved for the therapy of irinotecan resistant colorectal cancer and has been tested for pancreatic cancer. Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) are critical regulators of tumor angiogenesis. Bevacizumab (Avastin(TM)), a monoclonal antibody against VEGF, was efficient in two randomized clinical trials investigating the treatment of metastatic colorectal cancer. It is also currently investigated for the therapy of pancreatic cancer in combination with gemcitabine. Other promising new drugs currently under preclinical and clinical evaluation, are VEGFR2 inhibitor PTK787/ZK 222584, thalidomide, farnesyl transferase inhibitor R115777 (tipifarnib, Zarnestra(TM)), matrix metalloproteinase inhibitors, proteasome inhibitor bortezomib (Velcade(TM)), mammalian target of rapamycin (mTOR) inhibitors, cyclooxygenase-2 (COX-2) inhibitors, platelet derived growth factor receptor (PDGF-R) inhibitors, protein kinase C (PKC) inhibitors, mitogen-activated protein kinase kinase (MEK) 1/2 inhibitors, Rous sarcoma virus transforming oncogene (SRC) kinase inhibitors, histondeacetylase (HDAC) inhibitors, small hypoxia-inducible factor (HIF) inhibitors, aurora kinase inhibitors, hedgehog inhibitors, and TGF-beta signalling inhibitors.

Animals↗
PubMed2004

Interaction between trypsinogen isoforms in genetically determined pancreatitis: mutation E79K in cationic trypsin (PRSS1) causes increased transactivation of anionic trypsinogen (PRSS2).

The human pancreas secretes two major trypsinogen isoforms, cationic and anionic trypsinogen. To date, 19 genetic variants have been identified in the cationic trypsinogen gene (PRSS1) of patients with hereditary, familial, or sporadic chronic pancreatitis. A common feature of cationic trypsinogen mutants studied so far is an increased propensity for autocatalytic activation (autoactivation). This is thought to lead to premature intrapancreatic digestive protease activation. In contrast, no pancreatitis-associated mutations have been found in the anionic trypsinogen gene (PRSS2), suggesting that this isoform might play a relatively unimportant role in pancreatitis. To challenge this notion, here we describe the unique properties of the E79K cationic trypsinogen mutation (c.235G>A), which was identified in three European families affected by sporadic or familial pancreatitis cases. In vitro analysis of recombinant wild-type and mutant enzymes revealed that catalytic activity of E79K trypsin was normal, and its inhibition by pancreatic secretory trypsin inhibitor was unaffected. Although the E79K mutation introduces a potential new tryptic cleavage site, autocatalytic degradation (autolysis) of E79K-trypsin was also unchanged. Furthermore, in contrast to previously characterized disease-causing mutations, E79K markedly inhibited autoactivation of cationic trypsinogen. Remarkably, however, E79K trypsin activated anionic trypsinogen two-fold better than wild-type cationic trypsin did, while the common pancreatitis-associated mutants R122H or N29I had no such effect. The observations not only suggest a novel mechanism of action for pancreatitis-associated trypsinogen mutations, but also highlight the importance of interactions between the two major trypsinogen isoforms in the development of genetically determined chronic pancreatitis.

Adult↗
PubMed2004

Photodynamic therapy in patients with non-resectable hilar cholangiocarcinoma: 5-year follow-up of a prospective phase II study.

BACKGROUND: Median survival of patients with non-resectable hilar cholangiocarcinoma is 3 to 6 months, even after biliary drainage. Therefore, a single-arm phase II study was conducted (July 1996 to October 1998) to investigate the effect of local photodynamic therapy; a significant improvement in survival (74%) was noted at 6 months. The present study is an analysis of the long-term follow-up for patients enrolled in that phase II study. METHODS: Five-year follow-up data for the 23 patients enrolled in the original prospective study were analyzed by using Kaplan-Meier log-rank analysis. RESULTS: Median survival after treatment was 11.2 months for patients without distant metastases (M0) and 9.3 months for all patients (M0+M1). The 1-year, 2-year, 3-year, and 4-year survival rates were estimated to be 47%, 21%, 11% and 5%, respectively, for patients with stage M0 cholangiocarcinoma, and 39%, 17%, 9%, and 4%, respectively, for patients with stages M0 and M1. Of the patients who died, 73.9% (n=17) were because of tumor progression; 26.1% (n=6) died as a result of cholangitis (n=4), septic shock (n=1), or appendicitis/peritonitis (n=1). For all patients, except one with diffuse liver metastases, there was improvement in cholestasis, performance, and quality of life, which was maintained for an extended period. CONCLUSIONS: This 5-year follow-up study confirms that photodynamic therapy is safe and effective for non-resectable hilar cholangiocarcinoma, although it does not prevent progression of the disease.

Adult↗
PubMed2004

Combined percutaneous transhepatic biliary drainage with port implantation for management of patients with malignant biliary obstruction.

BACKGROUND: Endoscopic biliary stent insertion has become a standard palliative treatment for patients with obstructive jaundice caused by malignancies of the hepatobiliary system or metastases of other tumors, such as pancreatic or gastric cancer. Unfortunately, bacterial colonization and encrustation frequently leads to occlusion of plastic stents and, consequently, recurrent cholangitis. METHODS: An external-internal Yamakawa-type endoprosthesis was modified and combined with a titanium, subcutaneously implanted port. This technique was evaluated as a new approach to prolongation of stent patency and prevention of cholangitis. Two patients with obstructive jaundice, one with recurrent gastric carcinoma and the other with invasive gallbladder cancer, underwent treatment with this new method. RESULTS: Effective biliary drainage was established and cholangitis was prevented in both patients for 6 and 2 months, respectively. CONCLUSIONS: A new method of percutaneous transhepatic drainage combined with port implantation was effective and safe in two patients. This technique may be a reasonable treatment option for selected patients, but further evaluation in a larger series is required to establish efficacy and safety.

Aged↗
PubMed2004

Rapid detection of mutations in Wilson disease gene ATP7B by DNA strip technology.

Wilson disease leads to severe hepatic and neurological pathology resulting from cellular copper overload in the respective tissue. Although the affected gene, ATP7B, has been identified, genetic testing is challenging, time-consuming and expensive. Here we describe the development and use of a novel diagnostic test for four frequent mutations (M769V, W779X, H1069Q and P1134P-fs) found in Germany and many other countries in Europe. The test is based on multiplex polymerase chain reaction and DNA strip technology and was found to be highly sensitive and specific, as well as timely and cost-effective. We conclude that this test is a useful and reliable tool to screen Wilson disease patients and their family members for these mutations and may facilitate diagnosis in this complex disease.

Adenosine Triphosphatases↗
PubMed2004

General principles of photodynamic therapy (PDT) and gastrointestinal applications.

The purpose of this review article is to describe the history of photodynamic therapy (PDT), its current medical applications, the mechanism of action, contraindications of the method, and different types of photosensitizers used. The second part of the article deals with applications for gastrointestinal diseases. The treatment of obstructing oesophageal cancer, early-stage oesophageal cancer, Barrett's esophagus, hilar cholangiocarcinoma, stomach-, colon- and pancreatic cancer are discussed. The final part focuses on future directions of PDT like certain innovative ideas, which are currently under investigation.

Animals↗