Perioperative or only adjuvant gemcitabine plus nab-paclitaxel for resectable pancreatic cancer (NEONAX)-a randomized phase II trial of the AIO pancreatic cancer group

BACKGROUND

Data on perioperative chemotherapy in resectable pancreatic ductal adenocarcinoma (rPDAC) are limited. NEONAX examined perioperative or adjuvant chemotherapy with gemcitabine plus nab-paclitaxel in rPDAC (National Comprehensive Cancer Network criteria).

PATIENTS AND METHODS

NEONAX is a prospective, randomized phase II trial with two independent experimental arms. One hundred twenty-seven rPDAC patients in 22 German centers were randomized 1 : 1 to perioperative (two pre-operative and four post-operative cycles, arm A) or adjuvant (six cycles, arm B) gemcitabine (1000 mg/m2) and nab-paclitaxel (125 mg/m2) on days 1, 8 and 15 of a 28-day cycle.

RESULTS

The primary endpoint was disease-free survival (DFS) at 18 months in the modified intention-to-treat (ITT) population [R0/R1-resected patients who started neoadjuvant chemotherapy (CTX) (A) or adjuvant CTX (B)]. The pre-defined DFS rate of 55% at 18 months was not reached in both arms [A: 33.3% (95% confidence interval [CI] 18.5% to 48.1%), B: 41.4% (95% CI 20.7% to 62.0%)]. Ninety percent of patients in arm A completed neoadjuvant treatment, and 42% of patients in arm B started adjuvant chemotherapy. R0 resection rate was 88% (arm A) and 67% (arm B), respectively. Median overall survival (mOS) (ITT population) as a secondary endpoint was 25.5 months (95% CI 19.7-29.7 months) in arm A and 16.7 months (95% CI 11.6-22.2 months) in the upfront surgery arm. This difference corresponds to a median DFS (mDFS) (ITT) of 11.5 months (95% CI 8.8-14.5 months) in arm A and 5.9 months (95% CI 3.6-11.5 months) in arm B. Treatment was safe and well tolerable in both arms.

CONCLUSIONS

The primary endpoint, DFS rate of 55% at 18 months (mITT population), was not reached in either arm of the trial and numerically favored the upfront surgery arm B. mOS (ITT population), a secondary endpoint, numerically favored the neoadjuvant arm A [25.5 months (95% CI 19.7-29.7months); arm B 16.7 months (95% CI 11.6-22.2 months)]. There was a difference in chemotherapy exposure with 90% of patients in arm A completing pre-operative chemotherapy and 58% of patients starting adjuvant chemotherapy in arm B. Neoadjuvant/perioperative treatment is a novel option for patients with resectable PDAC. However, the optimal treatment regimen has yet to be defined. The trial is registered with ClinicalTrials.gov (NCT02047513) and the European Clinical Trials Database (EudraCT 2013-005559-34).

CCL17 Promotes Colitis-Associated Tumorigenesis Dependent on the Microbiota

Colorectal cancer is one of the most common cancers and a major cause of mortality. Proinflammatory and antitumor immune responses play critical roles in colitis-associated colon cancer. CCL17, a chemokine of the C-C family and ligand for CCR4, is expressed by intestinal dendritic cells in the steady state and is upregulated during colitis in mouse models and inflammatory bowel disease patients. In this study, we investigated the expression pattern and functional relevance of CCL17 for colitis-associated colon tumor development using CCL17-enhanced GFP-knockin mice. CCL17 was highly expressed by dendritic cells but also upregulated in macrophages and intermediary monocytes in colon tumors induced by exposure to azoxymethane and dextran sodium sulfate. Despite a similar degree of inflammation in the colon, CCL17-deficient mice developed fewer tumors than did CCL17-competent mice. This protective effect was abrogated by cohousing, indicating a dependency on the microbiota. Changes in microbiota diversity and composition were detected in separately housed CCL17-deficient mice, and these mice were more susceptible to azoxymethane-induced early apoptosis in the colon affecting tumor initiation. Immune cell infiltration in colitis-induced colon tumors was not affected by the lack of CCL17. Taken together, our results indicate that CCL17 promotes colitis-associated tumorigenesis by influencing the composition of the intestinal microbiome and reducing apoptosis during tumor initiation.

Chemokine receptor 8 expression may be linked to disease severity and elevated interleukin 6 secretion in acute pancreatitis

BACKGROUND

Acute pancreatitis (AP) is an inflammatory disease, which presents with epigastric pain and is clinically diagnosed by amylase and lipase three times the upper limit of normal. The 2012 Atlanta classification stratifies the severity of AP as one of three risk categories namely, mild AP (MAP), moderately severe AP (MSAP), and severe AP (SAP). Challenges in stratifying AP upon diagnosis suggest that a better understanding of the underlying complex pathophysiology may be beneficial.

AIM

To identify the role of the chemokine receptor 8 (CCR8), expressed by T-helper type-2 Lymphocytes and peritoneal macrophages, and its possible association to Interleukin (IL)-6 and AP stratification.

METHODS

This study was a prospective case-control study. A total of 40 patients were recruited from the Chris Hani Baragwanath Academic Hospital and the Charlotte Maxeke Johannesburg Academic Hospital. Bioassays were performed on 29 patients (14 MAP, 11 MSAP, and 4 SAP) and 6 healthy controls as part of a preliminary study. A total of 12 mL of blood samples were collected at Day (D) 1, 3, 5, and 7 post epigastric pain. Using multiplex immunoassay panels, real-time polymerase chain reaction (qRT-PCR) arrays, and multicolour flow cytometry analysis, immune response-related proteins, genes, and cells were profiled respectively. GraphPad Prism™ software and fold change (FC) analysis was used to determine differences between the groups. P<0.05 was considered significant.

RESULTS

The concentration of IL-6 was significantly different at D3 post epigastric pain in both the MAP group and MSAP group with P = 0.001 and P = 0.013 respectively, in a multiplex assay. When a FC of 2 was applied to identify differentially expressed genes using RT² Profiler, CCR8 was shown to increase steadily with disease severity from MAP (1.33), MSAP (38.28) to SAP (1172.45) median FC. Further verification studies using RT-PCR showed fold change increases of CCR8 in MSAP and SAP ranging from 1000 to 1000000 times when represented as Log₁₀, compared to healthy control respectively at D3. The findings also showed differing lymphocyte and monocyte cell frequency between the groups. With monocyte population frequency as high as 70% in MSAP at D3.

CONCLUSION

The higher levels of CCR8 and IL-6 in the severe patients and immune cell differences compared to MAP and controls provide an avenue for exploring AP stratification to improve management.

Rational design, synthesis and testing of novel tricyclic topoisomerase inhibitors for the treatment of bacterial infections part 1

The alarming reduction in drug effectiveness against bacterial infections has created an urgent need for the development of new antibacterial agents that circumvent bacterial resistance mechanisms. We report here a series of DNA gyrase and topoisomerase IV inhibitors that demonstrate potent activity against a range of Gram-positive and selected Gram-negative organisms, including clinically-relevant and drug-resistant strains. In part 1, we present a detailed structure activity relationship (SAR) analysis that led to the discovery of our previously disclosed compound, REDX05931, which has a minimum inhibitory concentration (MIC) of 0.06 μg mL^-1 against fluoroquinolone-resistant Staphylococcus aureus. Although in vitro hERG and CYP inhibition precluded further development, it validates a rational design approach to address this urgent unmet medical need and provides a scaffold for further optimisation, which is presented in part 2.

Association of infra-patellar fat pad size with age and body weight in children and adolescents

BACKGROUND

The infra-patellar fat pad (IPFP) represents a potential mediator between obesity, low grade inflammation, and knee osteoarthritis via endocrine pathways. Yet, not only in adults, but also in childhood obesity negatively impacts knee structures.

OBJECTIVE

The current study therefore investigated the sex-specific growth of the IPFP with age and body weight in healthy children and adolescents.

MATERIALS AND METHODS

Thirty young healthy subjects (60% girls; age 4-17 years, body weight 14-90 kg in girls and 29-105 kg in boys; BMI 12.2-32.4 kg/m²) without magnetic resonance imaging (MRI) knee pathology were studied. The IPFP volume was determined from sagittal T-1 weighted and proton-density spectral attenuated inversion recovery MRIs. The primary analysis focused on the sex-specific IPFP volume/body weight ratio as dependent, and age as independent variable, using linear regression models. A secondary analytic focus was the slope of the age-dependence of IPFP volume, without normalization to body weight.

RESULTS

There was no statistically significant association of the IPFP volume/body weight ratio with age in girls (p = 0.57) or boys (p = 0.31), the R² of ranging from -0.32 to 0.14. The ratio was greater in boys (0.54 ± 0.10 cm³/kg) than in girls (0.45 ± 0.07 cm³/kg) (p < 0.01). The IPFP volume increased by approx. 2 cm³ per annum in both girls and boys, without any indication of a non-linear relationship.

CONCLUSION

Our findings reveal that the ratio of the IPFP volume and body weight remains constant between age 4 and 17 in both normal weight girls and boys, and that the IPFP volume increases linearly with age throughout this period.

Increased Incidence of Colon Tumors in AOM-Treated Apc 1638N/+ Mice Reveals Higher Frequency of Tumor Associated Neutrophils in Colon Than Small Intestine

Colorectal cancer (CRC) is one of the most common cancers and a major cause of mortality. Mice with truncating Apc germline mutations have been used as a standard model of CRC, but most of the Apc-mutated lines develop multiple tumors in the proximal small intestine and rarely in the colon precluding detailed analysis of colon tumor microenvironment. Our aim was to develop a model with higher resemblance to human CRC and to characterize tumor infiltrating immune cells in spontaneously developing colon tumors compared to small intestinal tumors. Therefore, the Apc^1638N/+ line was treated repeatedly with azoxymethane (AOM) and 90% colon tumor incidence and 4 to 5 colon tumors per mouse were achieved. Of note, AOM treatment specifically increased the tumor burden in the colon, but not in the small intestine. Histological grading and WNT-signaling activity did not differ significantly between small intestinal and colon tumors with some lesions progressing to invasive adenocarcinoma in both locations. However, characterization of the intratumoral myeloid cell compartment revealed a massive infiltration of colon tumors with neutrophils − 6-fold higher than in small intestinal tumors. Moreover, CCL17-expressing macrophages and dendritic cells accumulated in the tumors indicating the establishment of a tumor-promoting immunosuppressive environment. Thus, Apc^1638N/+ mice treated with AOM are a suitable and straightforward model to study the influence of immune cells and chemokines on colon carcinogenesis.

Comparison of iron-reduced and iron-supplemented semisynthetic diets in T cell transfer colitis

Clinical observations in inflammatory bowel disease patients and experimental studies in rodents suggest that iron in the intestinal lumen derived from iron-rich food or oral iron supplementation could exacerbate inflammation and that iron depletion from the diet could be protective. To test the hypothesis that dietary iron reduction is protective against colitis development, the impact of iron reduction in the diet below 10 mg/kg on the course of CD4+ CD62L+ T cell transfer colitis was investigated in adult C57BL/6 mice. Weight loss as well as clinical and histological signs of inflammation were comparable between mice pretreated with semisynthetic diets with either < 10mg/kg iron content or supplemented with 180 mg/kg iron in the form of ferrous sulfate or hemin. Accumulation and activation of Ly6C^high monocytes, changes in dendritic cell subset composition and induction of proinflammatory Th1/Th17 cells in the inflamed colon were not affected by the iron content of the diets. Thus, dietary iron reduction did not protect adult mice against severe intestinal inflammation in T cell transfer induced colitis.

Risk for transmission of Naegleria fowleri from solid organ transplantation

Primary amebic meningoencephalitis (PAM) caused by the free-living ameba (FLA) Naegleria fowleri is a rare but rapidly fatal disease of the central nervous system (CNS) affecting predominantly young, previously healthy persons. No effective chemotherapeutic prophylaxis or treatment has been identified. Recently, three transplant-associated clusters of encephalitis caused by another FLA, Balamuthia mandrillaris, have occurred, prompting questions regarding the suitability of extra-CNS solid organ transplantation from donors with PAM. During 1995-2012, 21 transplant recipients of solid organs donated by five patients with fatal cases of PAM were reported in the United States. None of the recipients developed PAM, and several recipients tested negative for N. fowleri by serology. However, historical PAM case reports and animal experiments with N. fowleri, combined with new postmortem findings from four patients with PAM, suggest that extra-CNS dissemination of N. fowleri can occur and might pose a risk for disease transmission via transplantation. The risks of transplantation with an organ possibly harboring N. fowleri should be carefully weighed for each individual recipient against the potentially greater risk of delaying transplantation while waiting for another suitable organ. In this article, we present a case series and review existing data to inform such risk assessments.

Vascular endothelial growth factor expression following ischemic conditioning of the gastric conduit

The partial devascularization of the stomach, necessary for esophageal reconstruction with a gastric conduit, impairs microcirculation in the anastomotic region of the gastric fundus. Ischemic conditioning of the gastric tube is considered as a possible approach to improve microcirculation in the gastric mucosa. The aim of this study was to investigate whether ischemic conditioning induces neo-angiogenesis in the gastric fundus by expression of vascular endothelial growth factor (VEGF). Twenty patients with an esophageal carcinoma scheduled for esophagectomy and gastric reconstruction were included. To compare VEGF expression before and after ischemic conditioning, preoperative endoscopic biopsies were taken from the gastric fundus. The surgical procedure consisted of two separate steps, the complete gastric mobilization including partial devascularization of the stomach and after a delay of 4-5 days high transthoracic esophagectomy with intrathoracic gastric reconstruction (Ivor-Lewis procedure). The second tissue sample was obtained from the donut of the stapled esophagogastrostomy. For further work-up, preoperative biopsies and the gastric donuts were fixed in liquid nitrogen. Preoperative and intraoperative VEGF expression was measured by quantitative real-time reverse transcription-polymerase chain reaction (VEGF×100/β-actin) and results were compared using Wilcoxon test for paired samples. In all 40 specimens, a distinct expression of VEGF could be detected. Comparing the level of VEGF expression of the preoperative biopsies and postoperative tissue sample, no significant difference could be demonstrated following ischemic conditioning. In this model of ischemic conditioning with delayed reconstruction of 4-5 days, no induction of neo-angiogenesis could be demonstrated by measurement of VEGF expression.

The prognostic impact of extracapsular lymph node involvement in rectal cancer patients: Implications for staging and adjuvant treatment strategies

Limited data suggest that extracapsular lymph node involvement (LNI) has a negative prognostic impact in gastrointestinal malignancies. The aim of this study was to assess the prevalence and prognostic impact of LNI in patients with primary resected rectal cancer. Between 1997 and 2007, 243 rectal cancer patients underwent surgical therapy without neoadjuvant treatment at our Department. Of these, 12 (5%) patients received transanal endoscopic microsurgery and were not included for further analyses. In the remaining patients, a (low) anterior resection was performed in 79% and an abdominoperineal rectal amputation in 21%. The total number of analyzed lymph nodes and the number of metastatic lymph nodes with/without extracapsular LNI were determined and the prognostic impact of LNI was assessed. The median number of analyzed lymph nodes was 14. In total, 59% of patients were node-negative, 18% of patients were node-positive without extracapsular LNI and 23% of patients were node-positive with extracapsular LNI. A positive lymph node status with extracapsular LNI was significantly correlated with a poorer T-, N- and M-category, grading and more frequent lymphatic vessel infiltration compared with node-negative or node-positive without extracapsular LNI patients (p<0.001). The overall 5-year survival rate of node-negative patients was 75%, for node-positive without extracapsular LNI patients 69% and for node-positive with extracapsular LNI patients 36% (p<0.001). By multivariate analysis, the N-category with extracapsular LNI was characterized as an independent prognostic factor. Extracapsular lymph node involvement reveals an independent negative prognostic impact in patients with rectal cancer undergoing surgical therapy. Staging systems for rectal cancer should include the implementation of extracapsular lymph node involvement.

Reduced oxygen stress promotes propagation of murine postnatal enteric neural progenitors in vitro

BACKGROUND

Neural stem and progenitor cells of the Enteric Nervous System (ENS) are regarded as a novel cell source for applications in regenerative medicine. However, improvements to the current ENS cell culture protocols will be necessary to generate clinically useful cell numbers under defined culture conditions. Beneficial effects of physiologically low oxygen concentrations and/or the addition of anti-oxidants on propagation of various types of stem cells have previously been demonstrated. In this study, we tested the effects of such culture conditions on ENS stem and progenitor cell behavior.

METHODS

Enteric neural progenitor cells were isolated from postnatal day 3 mouse intestine and propagated either as monolayers or neurosphere-like bodies. The influence of hypoxic culture conditions and/or anti-oxidants on enteric cell propagation were studied systematically using proliferation, differentiation and apoptosis assays, whereas effects on gene expression were determined by qRT-PCR, western blot, and immunocytochemistry.

KEY RESULTS

Both hypoxic culture conditions and anti-oxidants supported a significantly improved enteric cell propagation and the generation of differentiated neural cell types. Enteric neural progenitors were shown to be specifically vulnerable to persistent oxidative stress.

CONCLUSIONS & INFERENCES

Our findings are consistent with previous reports of improved maintenance of brain stem cells cultured under reduced oxygen stress conditions and may therefore be applied to future cell culture protocols in ENS stem cell research.

[Cystic abdominal mass as a complication due to posterior urethral valves]

A case of urinoma with posterior urethral valves and its management is presented. Diagnostic investigations and therapy strategies are discussed. Though rare, this possibility should be considered in the differential diagnosis of neonates presenting with rapidly expanding cystic masses in the abdomen. Early diagnosis and management are the most important prognostic factors that ensure a good outcome in such cases.

[18F]-fluorodeoxyglucose-positron emission tomography for the assessment of histopathologic response and prognosis after completion of neoadjuvant chemotherapy in gastric cancer

BACKGROUND AND OBJECTIVES

Neoadjuvant chemotherapy is applied to improve the prognosis of patients with advanced gastric cancer. However, only a major histopathological response will provide a benefit. Recent studies suggest that [(18)F]-fluorodeoxyglucose-positron-emission-tomography (FDG-PET) correlates with response and survival in patients with gastroesophageal adenocarcinomas undergoing neoadjuvant chemotherapy. We evaluated the potential of FDG-PET for the assessment of response and prognosis in the multimodality treatment of gastric cancer.

METHODS

Study patients were recruited from a prospective observation trial. Forty two patients with advanced gastric cancer received neoadjuvant chemotherapy and subsequently 40 patients underwent standardized gastrectomy (2 patients with tumor progression had therapy limited to palliative chemotherapy without surgery). Histomorphologic regression was defined as major response when resected specimens contained <10% vital tumor cells. FDG-PET was performed before and 2 weeks after the end of neoadjuvant chemotherapy with assessment of the intratumoral FDG-uptake [pre-treatment standardized uptake value (SUV1); post-treatment SUV (SUV2); percentage change (SUVDelta%)].

RESULTS

Histomorphological tumor regression was confirmed as a prognostic factor (P = 0.039). No significant correlations between SUV1, SUV2, or SUVDelta% and response or prognosis were found.

CONCLUSION

FDG-PET seems not to be an imaging system that effectively characterizes major/minor response and survival in patients with gastric cancer following multimodality treatment.

[Thoracic surgery in neonates and infants with congenital malformations]

Congenital malformations of the lung and diaphragm are a challenge in paediatric surgery. Depending on the malformation they show a broad spectrum of symptoms and a varying age at manifestation. Thus there are many diagnostic and therapeutic options, which require a good knowledge of the pathology. The treatment of these complex cases should lead to early referral to paediatric centres containing an interdisciplinary team with neonatologists, paediatric pulmonologists and cardiologists, ENT surgeons, anaesthesiologists, radiologists and paediatric surgeons. Some malformations are diagnosed prenatally and need intrauterine interventions. Decisive is the early diagnosis and treatment of these malformations. Nowadays the surgical therapy of neonates and infants with malformations of the lung and diaphragm is enriched by a number of endoscopic and endoluminal techniques, which are discussed critically in this article.

Survivin expression in gastric cancer: Association with histomorphological response to neoadjuvant therapy and prognosis

BACKGROUND AND OBJECTIVES

Neoadjuvant therapy is applied to improve the prognosis associated with advanced gastric cancer. Only patients with a major response seem to have a survival benefit. Predictive markers to allow individualisation of treatment could be helpful. We examined the association of survivin protein expression with histopathologic response to neoadjuvant chemotherapy and prognosis in patients with gastric cancer.

METHODS

Forty patients with gastric cancer received neoadjuvant chemotherapy. Afterwards, 38 patients underwent total gastrectomy, while 2 patients received definitive chemotherapy because of tumour progression. Histomorphologic regression was defined as major response when resected specimens contained <10% tumour cells. Intratumoural survivin expression was determined by immunohistochemistry in pre- and post-therapeutic specimens and correlated with clinicopathologic parameters.

RESULTS

The pre- and post-therapeutic intratumoural survivin protein expression was not associated with histomorphologic regression. Post-therapeutic survivin expression did not have prognostic impact. A significant association was detected between pre-therapeutic survivin levels and prognosis: patients with a higher survivin protein expression showed a significant survival benefit. In multivariate analysis pre-therapeutic survivin expression was characterised as an independent prognostic marker, besides pN-status and histopathologic regression.

CONCLUSIONS

The pre-therapeutic survivin protein expression seems to be an independent prognostic marker in the multimodality treatment of advanced gastric cancer.

Evaluation of response in the multimodality treatment of esophageal cancer by [18F]-fluorodeoxyglucose-positron emission tomography: A systematic review and meta-analysis

e15520

Background: Neoadjuvant therapy followed by surgery is frequently applied to improve the prognosis of patients with esophageal cancer. However, only a major histopathological response will provide a survival benefit. On the other hand, evidence suggests that patients with response to chemoradiation have no additional benefit from surgery compared with definitive chemoradiation. Consequently, effective methods for early and late response assessment are required in order to perform these different individualised, response-guided treatment concepts. The value of [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) for this diagnostic purpose is still under debate. This systematic review and meta-analysis aims to evaluate the potential of FDG-PETfor the assessment of response in the multimodality treatment of patients with esophageal cancer. Methods: A systematic literature search of studies published between 1990 and September 2008 was performed. The meta-analysis estimated the pooled sensitivity and specificity of histopathological response assessment by FDG-PET using a random effect model. Results: Thirty relevant studies with 1151 patients (865 adenocarcinoma, 493 squamous cell cancer) were identified and included in the systematic review. Mainly neoadjuvant chemoradiation (22 studies) was performed. FDG-PET was conducted mostly before and after neoadjuvant therapy (21 studies) and second most (6 studies) the subsequent FDG-PET was scheduled 7–14 days after the initiation of preoperative therapy. Sixteen studies were included in the meta-analysis. For metabolic response assessment 7–14 days after the initiation of therapy, including 254 patients (with 5 studies from one center), the pooled sensitivity was 85.5% (95% CI: 75.5%-92.8%) and specificity 76.1% (95% CI: 69.3%-82.0%). For late response assessment, including 446 patients, the pooled sensitivity was 77.1% (95% CI: 72.8%- 81.0%) and specificity 59.0% (95% CI: 55.3%-62.7%). Conclusions: For early response assessment FDP-PET seems to be useful in the multimodality treatment of esophageal cancer. In contrast, this study suggests FDG-PET invaluable for late response assessment.

No significant financial relationships to disclose.

GNAS1 T393C polymorphism is associated with histopathological response to neoadjuvant radiochemotherapy in esophageal cancer

Recent studies have shown an association between the GNAS1 T393C polymorphism and clinical outcome for various solid tumors. In this study, we genotyped 51 patients from an observational trial on cisplatin/5-FU-based neoadjuvant radiochemotherapy of locally advanced esophageal cancer (cT2-4, Nx, M0) and genotyping was correlated with histomorphological tumor regression. The C-allele frequency in esophageal cancer patients was 0.49. Pearson's chi(2)-test showed a significant (P<0.05) association between tumor regression grades and T393C genotypes. Overall, 63% of the patients in the T-allele group (TT+CT) were minor responders with more than 10% residual vital tumor cells in resection specimens, whereas T(-) genotypes (CC) showed a major histopathological response with less than 10% residual vital tumor cells in 80%. The results support the role of the T393C polymorphism as a predictive molecular marker for tumor response to cisplatin/5-FU-based radiochemotherapy in esophageal cancer.

In vitro and in vivo evaluation of photodynamic techniques for the experimental treatment of human hepatoblastoma and neuroblastoma: preliminary results

PURPOSE

The purpose of this study was to test the susceptibility of human hepatoblastoma and neuroblastoma cells to photodynamic diagnostics (PDD) and photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA) as a photosensitizer.

METHODS

Cell cultures of human hepatoblastoma (HuH6) and neuroblastoma (MHH-NB-11) were incubated with 5-ALA at increasing concentrations to measure the cellular kinetics of photosensitization. After optimizing incubation parameters, the cell cultures were then irradiated with increasing light doses and cell viability was measured by CTB assay. Human fibroblastic cells served as controls. So far, only the hepatoblastoma cell line has been tested in vivo. After injection of HUH6 cells in immunoincompetent rats, the efficacy of PDT was assessed. Photosensitization was achieved by intraperitoneal injection of 5-ALA. The pharmacokinetics of different tissues was studied. In a second study, a PDT of implanted hepatoblastoma, liver and peritoneum was performed. The irradiated areas were excised 48 h after treatment and studied by microscopy.

RESULTS

Cell culture experiments demonstrated a selective fluorescence for both tumor lines compared to controls. The photosensitized tumor cells demonstrated marked reductions in cell viability at significantly lower irradiation doses than the fibroblasts under PDT. The specificity of fluorescence was confirmed in vivo for hepatoblastoma, and all the sensitized and irradiated tumors showed marked phototoxic necrosis.

CONCLUSION

Human hepatoblastoma and neuroblastoma demonstrate marked and specific fluorescence after the application of 5-ALA, making PDD possible. Cell death occurred in both cell lines after PDT in vitro. Additionally, hepatoblastoma was susceptible to PDT in an animal model. Further studies will be necessary to determine the role of PDT and PDD in a clinical setting.

Successful management of esophageal perforation due to an aortic arch aneurysm replacement

We present the successful management of an esophageal perforation after aortic arch aneurysm replacement in a 64-year-old patient. Four weeks after surgical repair of a perforated aortic arch aneurysm, a contained perforation of the thoracic esophagus on the prosthesis was detected. A subtotal esophagectomy and reconstruction by pull-up of the stomach together with the greater omentum and high intrathoracic esophagogastrostomy was performed. The aortic prosthesis was covered by omentum. After a prolonged postoperative course, the patient was discharged from the hospital on a full oral diet. She is well after 1 year without signs of infection.

Histological type of esophageal cancer might affect response to neo-adjuvant radiochemotherapy and subsequent prognosis

BACKGROUND

This study investigates response and prognosis after neo-adjuvant chemoradiation (CTx/RTx) in patients with advanced esophageal carcinoma, according to histological type.

PATIENTS AND METHODS

Patients with uT3 carcinoma of the esophagus treated with curative-intention esophagectomy from 1997 until 2006 were included in this retrospective analysis. Patients receiving preoperative CTx/RTx (5-fluorouracil, cisplatin, 36 Gy) were compared with those with primary surgery for pT3 tumors. Therapy response after CTx/RTx was evaluated using 'Cologne Regression Grade' (minor response: >or=10% vital residual tumor cells (VRTCs), major response: <10% VRTC or pathologic complete response). Prognosis was evaluated for adenocarcinoma (AC) and squamous cell carcinoma (SCC).

RESULTS

Of 297 patients, 52% were SCC and 48% AC. In all, 192 patients underwent CTx/RTx, 100 (65%) SCC and 92 (64%) AC (nonsignificant). In SCC group 51% and in AC group 29% achieved major response (P < 0.01). Patients with major response had a 2-year survival rate (2y-SR) of 78% versus those with minor response or without CTx/RTx, with a 2y-SR of 45% (P = 0.001). Examining patients with major response exclusively, the prognosis of AC (2y-SR 85%) is better than that of SCC (2y-SR 54%) (P < 0.01).

CONCLUSION

This retrospective study concludes that in esophageal tumors, response to and prognosis after neo-adjuvant CTx/RTx vary according to histology.

Serosal penetration is an important prognostic factor for gastrointestinal stromal tumors

Predicting the malignant potential of gastrointestinal stromal tumors (GISTs) remains difficult. We assessed the value of serosal penetration, an established prognostic factor in solid tumors, to determine the clinical outcome in patients with GISTs. From 1996-2002, 25 consecutive patients with GIST underwent surgical resection at our Department. The histopathological presence of serosal penetration was assessed to predict clinical outcome. In addition, the established histopathological classification system by Franquemont (modified by using the Ki-67 proliferation index), was applied to each study patient. A Ki-67 index > or =5% (p<0.001) and a mitotic rate > or =5/50 high-power fields (p<0.047) significantly correlated with a shorter survival, whereas a tumor size >5 cm (p=0.07) tended towards a worse prognosis. The survival of patient groups defined by Franquemont (p=0.03) were of prognostic relevance. The presence of serosal penetration significantly correlated (p<0.01) with a shorter survival. Our data suggest that the presence of serosal penetration is a negative prognostic factor for GISTs. Serosal penetration may become a useful additional parameter for the classification of the malignant potential of GISTs. Since our data are merely hypothesis-generating, serosal penetration should be evaluated in large prospective databases.

Epitope mapping of mAbs to denatured human testicular ACE (CD143)

Angiotensin I-converting enzyme (ACE; CD143) has two homologous enzymatically active domains (N and C) and plays a crucial role in blood pressure regulation and vascular remodeling. A wide spectrum of monoclonal antibodies (mAbs) to different epitopes on the N and C domains of human ACE have been used to study different aspects of ACE biology. In this study, we characterized a set of nine mAbs, developed against the C domain of human ACE, which recognize the denatured forms of ACE and thus are suitable for the detection and quantification of somatic ACE (sACE) and testicular ACE (tACE) using Western blotting and immunohistochemistry on paraffin-embedded human tissues. The epitopes for these mAbs were defined using species cross-reactivity, phage display library screening, Western blotting and ACE mutagenesis. Most of the mAbs recognized common/overlapping region(s) on both somatic and testicular forms of human ACE, whereas mAb 4E10 was relatively specific for the testicular isoform and mAb 5B9 mainly recognized the glycan attached to Asn 731. This set of mAbs is useful for identifying even subtle changes in human ACE conformation because of denaturation. These mAbs are also sensitive tools for the detection of human sACE and tACE in biological fluids and tissues using proteomic approaches. Their high reactivity in paraffin-embedded tissues provides opportunities to study changes in the pattern of ACE expression and glycosylation (particularly with mAb 5B9) in different tissues and cells.

Clinicopathological significance of MMP-2 and its specific inhibitor TIMP-2 in gastric cancer

Matrix metalloproteinases (MMPs) can degrade type IV collagen of extracellular matrices and basal membranes and thus play a key role in the migration of malignant cells. In vivo, MMPs are inhibited by tissue inhibitors of metalloproteinases (TIMPs). Since in a previous study we showed that the expression of MMP-2 correlates with clinicopathological parameters in gastric cancer, we have now investigated a possible correlation of MMP-2 and TIMP-2 expression with survival in gastric cancer, as well as the possible association of TIMP-2 with clinicopathological parameters. Tissue samples were obtained from 116 gastric cancer patients who underwent gastrectomy with extended lymphadenectomy. MMP-2 and TIMP-2 expression was analysed using immunohistochemical staining and was graded semiquantitatively (score 0 - 3). High epithelial MMP-2 immunoreactivity was significantly associated with tumor stage and poor survival using the Kaplan-Meier log-rank statistical method (log-rank statistics). However, using Cox regression analysis, high epithelial MMP-2 immunoreactivity was not an independent prognostic factor. TIMP-2 showed no association with survival in gastric cancer, but the intensity of TIMP-2 staining in tumor cells correlated significantly with tumor differentiation based on the WHO and Lauren and Ming classifications, as well as with presence of distant metastasis. Our results show that high epithelial MMP-2 expression in gastric cancer is associated with poor survival, although it is not an independent prognostic factor, and that aggressive forms of gastric cancer are associated with low TIMP-2 expression.

Foetal hepatocyte transplantation in a vascularized AV-Loop transplantation model in the rat

The use of foetal liver cells (FLC) in the context of hepatic tissue engineering might permit efficient in vitro expansion and cryopreservation in a cell bank. A prerequisite for successful application of bioartificial liver tissue is sufficient initial vascularization. In this study, we evaluated the transplantation of fibrin gel-immobilized FLC in a vascularized arterio-veno-venous (AV)-loop model. FLC were isolated from embryonic/foetal (ED 16) rat livers and were enriched by using magnetic cell sorting (MACS). After cryopreservation, FLC were labelled by pkh-26. Cells were transplanted in a fibrin matrix into a subcutaneous chamber containing a microsurgically created AV-loop in the femoral region of the recipient rat. The chambers were explanted after 14 days. Subcutaneous implants without an AV-loop and cell-free implants served as controls. Fluorescence microscopy of the constructs was used to identify pkh-26(+)- donor cells. Characterization was performed by RT-PCR and immunhistology (IH) for CK-18 and CD31. Transplantation of FLC using the AV-loop permitted a neo-tissue formation in the fibrin matrix. A high-density vascularization was observed in the AV-loop constructs as shown by CD31 IH. Viable foetal donor cells were detected which expressed CK-18. FLC can be successfully used for heterotopic transplantation. Fibrin matrix permits rapid blood vessel ingrowth from the AV-loop and supports engraftment of FLC. It is therefore an appropriate environment for hepatocyte transplantation in combination with microsurgical vascularization strategies. Transplantation of fibrin gel-immobilized FLC may be a promising approach for the development of highly vascularized in vivo tissue-engineering-based liver support systems.

Clinicopathologic and prognostic factors of young and elderly patients with esophageal adenocarcinoma: is there really a difference?

Evidence suggests a significant difference in the incidence, presentation, and outcome of young and elderly patients with esophageal adenocarcinoma. We aimed to compare clinicopathologic and prognostic factors of young and elderly patients with esophageal adenocarcinoma at a surgical department in Europe. From 1996 to 2006, 223 patients with a resectable esophageal adenocarcinoma were analyzed and divided in three groups: (i) patients <or=50 years (n = 40); (ii) patients between 50 and 70 years (n = 131); and (iii) patients >70 years (n = 52). Clinicopathological and prognostic factors were compared between these groups. The total number of patients with esophageal adenocarcinoma increased significantly. Although the total number of patients <or=50 years increased over the years, the proportion of young patients with esophageal adenocarcinoma was rather constant. The number of patients with a pT1-tumor was similar among all groups. Young patients had a significantly lower comorbidity and received more often a neoadjuvant radio-chemotherapy. The 5-year survival rate of young patients was significantly higher compared with elderly patients. In this European population, the total number of patients with adenocarcinoma of the esophagus increased dramatically in recent years, but the number of young patients remained rather constant. The better prognosis of young patients is mainly caused by less comorbidity and more frequent use of neoadjuvant therapy.

Long gap esophageal atresia and arterial circle of Willis variant leading to ischemic stroke during gastric transposition

In children, strokes occur with a frequency of 2 to 13 per 100,000. Risk factors include hematological, embolic and anatomical anomalies. But often the exact cause of strokes in pediatric patients remains unclear. We report here on a patient with long gap esophageal atresia, who suffered an ischemic stroke during gastric transposition. Postoperative assessment revealed a cerebral vascular variant of the circle of Willis. Follow-up clinical controls showed a favorable course. Today, at the age of 14 months, almost no neurological deficits are evident. To the best of our knowledge, no description of vascular cerebral complications combined with esophageal atresia can be found in the literature.

Comparative analysis of four histopathological classification systems to discriminate benign and malignant behaviour in gastrointestinal stromal tumors

The prognostic value of the four most common histopathological classification systems in gastrointestinal stromal tumors (GISTs) was evaluated retrospectively.

PATIENTS AND METHODS

Twenty-five consecutive patients with resected GIST and a follow-up of five years or more for surviving patients were included in this analysis. All the tumors were c-KIT (CD117) positive and were additionally re-evaluated for the number of mitoses per 50 high-power fields (HPF) and Ki-67 proliferation index. The four most commonly applied histopathological classification systems of the WHO, Franquemont (modified by using the Ki-67 proliferation index), Fletcher and Miettinen were applied to each patient.

RESULTS

The survival of patient groups classified by Franquemont (p = 0.03) and the WHO (p = 0.031) were of prognostic relevance, while the grouping of patients by classifications according to both, Fletcher and Miettinen did not show a significant prognostic value.

CONCLUSION

The classification systems of Franquemont (modified) or WHO appear to be advantageous for the evaluation of malignant potential and clinical outcome in patients with GISTs. Our data are merely hypothesis generating and should be validated in larger clinical studies.

Alterations of tumor and normal tissue of human lung cancer resection specimens after isolation perfusion

The isolation perfusion model, including transbronchial ventilation of human lung, offers the possibility to study pharmacological interactions under physiological conditions. In view of the increasing importance of targeted therapy of lung diseases, this model of perfusion might attract major interest, particularly, in lung cancer. Our study investigated physiological, histological, and immunohistochemical alterations of lung and tumor tissue during isolated perfusion of lung lobectomy specimens to explore potential limitations of this model. Right after resection, 16 human lung resection specimens for primary lung cancer were isolated, ventilated, and perfused under physiological conditions with a modified Krebs-Henseleit solution over a period of 10, 60, 90, 120, and 240 min. Perfusion pressure, pH, lung weight gain, and histological edema formation were measured continuously before and during perfusion. After perfusion, lung and tumor tissue was investigated by hematoxylin-and-eosin stained sections. Immunohistochemistry of NADH, PECAM-1, angiotensin-converting-enzyme and NF-kappabeta were performed to determine lung tissue viability and changes at the endothelial layer. We found that perfusion up to 120 min could be performed with completely stable physiological conditions. Beyond that time span, edema formation and weight gain of the resection specimen started and were followed by an increase in inspiratory pressure and pulmonary artery pressure. Perfusion of more than 4 h led to a significant edema formation in lung tissue accompanied by loss of viability and significant histological alterations. We conclude that isolated ventilation and perfusion of human lung resections within the setup chosen is reliable for pharmacological studies up to a period of 120 min. Thereafter, edema formation and endothelial damage develop and limit the interpretation and reliability of drug delivery studies.

Association of COX-2 expression with corresponding active and chronic inflammatory reactions in Barrett's metaplasia and progression to cancer

AIMS

Risk reduction for Barrett's cancer in individuals taking non-steroidal anti-inflammatory drugs has been reported. Cyclooxygenase (COX)-2, one of the inhibited enzymes, is putatively involved in Barrett's cancer pathogenesis. The aim of this study was to examine a possible association between COX-2 protein expression and the development and progression of the Barrett's metaplasia-dysplasia-carcinoma sequence and the type and degree of associated inflammatory reaction.

METHODS AND RESULTS

Squamous epithelium, metaplastic, low-grade, high-grade dysplastic lesions and tumour tissue of 49 resection specimens from patients with Barrett's adenocarcinoma were immunohistochemically analysed. Active and chronic inflammatory reactions were classified according to the Updated Sydney System. Within the Barrett's sequence, a significant progressive increase in COX-2 expression was identified (P < 0.0001). The most significant differences were detected between squamous epithelium and Barrett's metaplasia (P < 0.001) and from low- to high-grade dysplasia (P < 0.0001). Active and chronic inflammation were significantly different between squamous epithelium and Barrett's metaplasia (P < 0.0001), but not during further progression in the sequence.

CONCLUSIONS

Increasing COX-2 expression in Barrett's metaplasia is significantly associated with a change in the local inflammatory reaction, but not during further progression through dysplasia to cancer. This supports the potential of a chemoprevention strategy using COX-2 inhibitors independent of the extent and type of the inflammatory reaction in Barrett's oesophagus.

First Report of Pythium intermedium Causing Root Rot on Rosa canina Rootstock in France

Old cultivars of roses (Rosa spp.) established on Rosa canina as rootstock are grown in field collections in the repository at Gaillard in eastern France, close to the Swiss border. During June 2005 and July 2006, several rose plants in full vegetation were severely wilted, leading ultimately to plant death. Necrotic lesions were present on the roots, and marginal tissue was excised and incubated in the dark at 20°C on PARP V8 agar plates (1). Similar isolates were obtained in both years, which were inoculated within 4 days on V8 agar medium and incubated at 25°C. The pathogen colonies grew approximately 30 mm daily on V8 agar. Colonies on corn meal agar (CMA) (1) were submerged, with or without a vague radiate pattern on potato carrot agar. Main hyphae were as much as 7 μm wide. Sporangia and zoospores were not produced. Hyphal swellings as much as 25 μm in diameter were abundant, terminal, and sometimes intercalary, often forming regular, dense chains in basipetal succession at hyphal tips and readily liberated. The morphological characters matched those described for Pythium intermedium (2). DNA sequencing of the ITS rDNA (ITS1, ITS2, and 5.8S rDNA) was generated using primers ITS5 and ITS4 in primary PCR (35 cycles: 96°C for 1 min, 55°C for 1 min, and 72°C for 2 min) and sequencing reactions (1). All isolates yielded identical ITS sequences, which were identical to the ex-type strain of P. intermedium, CBS 266.38 (GenBank Accession No. AY598647). The ITS sequence was deposited as GenBank Accession No. EF078693 (National Center for Biotechnology Information, NCBI, Bethesda, MD). Pathogenicity testing was performed on 3-year-old Rosa canina rootstocks from clonal propagation in 25 cm in diameter and 40 cm deep pots of compost 297 (Ricoter, Aarberg, Switzerland). Five-day-old mycelial plugs of our isolates grown on CMA (1) were inoculated in two pots, and roots were mechanically wounded. Sterile plugs were used on two control plants set aside. All plants were kept for 2 weeks at 20°C in a glasshouse with sufficient watering. Extensive necrotic lesions developed on inoculated roots, and severe wilting and leaves drying out were also observed. The controls showed no symptoms. P. intermedium was reisolated from margins of root lesions, thus fulfilling the postulates of Koch. P. intermedium was originally isolated from dead plant material (2) but is known as a typical soil inhabitant. It also has been isolated from water and living material from numerous plant species, but never from the genus Rosa until now. To our knowledge, this is the first record of P. intermedium on Rosa spp. grafted on Rosa canina in France. References: (1) L. Belbahri et al. FEMS Microbiol Lett 255:209, 2006. (2) A. J. van der Plaats-Niterink. Stud. Mycol. 21:1, 1981.

Survivin expression in esophageal cancer: Association with histomorphological response to neoadjuvant therapy and prognosis

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Background: The poor prognosis associated with locally advanced esophageal cancer prompted an evaluation of combined modality treatments including neoadjuvant radiochemotherapy in combination with surgery. However, it has been well established that only patients with a complete pathological response to neoadjuvant therapy will have a significant survival benefit. Therefore, predictive markers to allow a tailored radiochemotherapy are needed. The aim of this study was to examine the association of the protein expression of survivin, an inhibitor of apoptosis, with histopathologic response to neoadjuvant radiochemotherapy and prognosis of patients with locally-advanced esophageal cancer. Methods: 59 patients with esophageal cancer (cT2–4, Nx, M0) received neoadjuvant radiochemotherapy (cisplatin, 5-FU, 36 Gy) followed by esophagectomy. Histomorphologic regression was defined as major response when resected specimens contained less than 10 % and as minor response when resected specimens contained more than 10 % of residual vital tumor cells. Pre- and post-therapeutic intratumoral protein expression of survivin was determined and correlated with clinicopathologic parameters. Results: The pre-therapeutic intratumoral survivin protein expression was not associated with any clinicopathologic factor, including histopathologic response and prognosis. Survivin protein expression was significantly reduced during neoadjuvant therapy, showing lower levels in post-therapeutic tumor samples (p<0.01). Higher postoperative survivin levels were significantly associated with a higher ypT-stage (p<0.009), a poorer histopathologic response (p<0.01) and a shorter overall survival (p<0.028). Conclusions: The intratumoral protein expression of survivin was significantly down-regulated during neoadjuvant therapy, whereas a higher survivin level after pre-operative therapy was significantly associated with a worse histopathologic response and prognosis. Therapeutic strategies which are able to reduce survivin expression or to block survivin mediated pathways might increase the histopathologic response rate and prognosis in the multimodal therapy of patients with locally-advanced esophageal cancer.

No significant financial relationships to disclose.

Tumor model for laparoscopy in pediatric oncology: subperitoneal inoculation of human hepatoblastoma cells in nude rats

BACKGROUND

Minimally invasive surgery (MIS) for diagnostic or even ablative purposes in pediatric oncology is gradually evolving, but little is known about its biological consequences and surgical complications. Especially for hepatoblastoma (HB), no study on the influence of laparoscopy is available yet. A special tumor model could facilitate a variety of investigations. The present study introduces a laparoscopic technique to create subperitoneal metastases of human HB.

METHODS

7 immuno-incompetent (rnu/rnu) rats (mean weight 198 g) received a stab incision in the lower abdomen to insert a 4 mm scope. Under laparoscopic guidance (CO2 pressure of 1 mmHg, flow of 0.2 l/min) an 18 G needle was introduced, to inject several subperitoneal deposits of the tumor cell suspension (HuH6, 3 x 10 (6) in 1 ml of RPMI-1640 medium). Tumor growth was allowed for 6 - 7 weeks and finally the animals were laparoscopically evaluated for peritoneal metastases. Each suspicious lesion was harvested for histology.

RESULTS

One animal was investigated after 6 weeks without evidence of tumor growth. After 7 weeks, in 4 out of 6 animals at least one lesion could be detected. Histology revealed HB in all specimens.

CONCLUSION

Subperitoneal inoculation of human HB cells in nude rats achieves intraabdominal tumor growth. The present model allows a variety of laparoscopic strategies and their oncological impact to be studied. Thus it may contribute to the development of distinct oncological concepts for MIS in children with HB.

Monoclonal antibodies to native mouse angiotensin-converting enzyme (CD143): ACE expression quantification, lung endothelial cell targeting and gene delivery

We demonstrated previously that the monoclonal antibody 9B9 to angiotensin-converting enzyme (ACE), which accumulates very selectively into the rat lung after systemic injection, is a powerful tool for immunotargeting of therapeutic agents or genes to the rat lung vascular bed. Bearing in mind a high research and therapeutic potential of lung targeting via ACE, we obtained a new set of rat monoclonal antibodies to different epitopes of mouse ACE in order to expand this approach to mice. Nine new monoclonal antibodies, recognizing epitopes on the N- and C-domains of catalytically active mouse ACE, were obtained and examined for their efficacy to bind ACE both in vitro and in vivo. This set of monoclonal antibodies was proved to be useful for ACE quantification (by flow cytometry and cell enzyme-linked immunosorbent assay) on the surface of different mouse ACE-expressing cells: endothelial cells, monocytes, macrophages, dendritic cells and spermatozoa. Moreover, gene delivery into mouse ACE-expressing cells using adenoviruses increased 40-fold after redirecting of these viruses to ACE (by coating these viruses with anti-ACE monoclonal antibodies). Radiolabelled (I(125)) monoclonal antibodies specifically accumulated in the mouse lung after systemic injection. Monoclonal antibodies 3G8.17, 4B10.5 and 4B10.17 demonstrated the highest level of lung uptake, 40-50% of injected dose, and high selectivity of lung uptake. Influence of monoclonal antibodies on ACE shedding was negligible, except monoclonal antibody 1D10.11. None of the tested monoclonal antibodies inhibited ACE activity in vitro. In conclusion, a new set of rat monoclonal antibodies to mouse ACE was obtained suitable to study ACE biology in mice and for ACE expression quantification on mouse cells in particular. These monoclonal antibodies also demonstrated highly efficient and selective lung accumulation and thus has the potential for targeting drugs/genes to the pulmonary vasculature in different mouse models of human lung diseases, including numerous knockout models.

Survivin mRNA in peripheral blood is frequently detected and significantly decreased following resection of gastrointestinal cancers

BACKGROUND AND OBJECTIVES

We evaluated if mRNA expression of survivin, an inhibitor of apoptosis, can be used to detect circulating tumor cells in peripheral blood of patients with various gastrointestinal cancers and if they decrease following complete surgical resection.

METHODS

Blood samples from 40 gastrointestinal cancer patients were analyzed prior and following surgical resection by direct quantitative real-time reverse transcriptase-PCR (RT-PCR) assays.

RESULTS

Survivin mRNA expression was pre-operatively detected in 35 of 40 cancer patients (88%). Post-operative survivin levels were significantly lower than pre-operative levels in 59% of resected patients and were non-detectable in 38% (Wilcoxon rank test: P < 0.04).

CONCLUSIONS

This is the first report showing that direct quantitative real-time RT-PCR analysis of survivin mRNA expression in peripheral blood of patients with gastrointestinal cancers is technically feasible. Survivin mRNA levels fall significantly following complete resection and might become a molecular marker for the completeness of surgical resection.

Videoscopic fluorescence diagnosis of peritoneal and thoracic metastases from human hepatoblastoma in nude rats

BACKGROUND

Various medical disciplines are employing photodynamic diagnosis (PDD) when searching for malignancies. It is still unknown whether pediatric solid tumors such as hepatoblastoma are susceptible to this technique as well.

METHODS

Human hepatoblastoma cells were injected into the abdomen or right thoracic cavity of nude rats. Tumor growth was allowed for 7 weeks. Then, photosensitization was induced by peritoneal lavage with 5-aminolevulinic acid (ALA). Applying the Storz PDD system and one 4-mm scope, all animals were investigated by videoscopic white light diagnosis (WD) and PDD. Suspicious lesions were marked and analyzed by spectrometry and histology.

RESULTS

Positive fluorescence was documented for every tumor seen by WD in the abdomen or right thoracic cavity. Spectrometry of lesions showed a 6.34-fold increased fluorescence intensity. Histology revealed hepatoblastoma in all specimens.

CONCLUSIONS

Human hepatoblastoma can be detected by PDD in a rat model. Considering the clinical success of this method in other specialties, our findings indicate that further investigations to evaluate the benefit of PDD for children with hepatoblastoma should be performed.

[Psychiatric-psychotherapeutic inpatient treatment for depression. Process and outcome quality based on a model project in Baden-Wurttemberg]

During 1998-2000 a quality assurance program for diagnosis and treatment of depression was conducted in 24 hospitals for psychiatry and psychotherapy in Baden-Wurttemberg (southern Germany). Process and outcome quality of 3,000 depressive patients was documented at admission and discharge. The article focuses on therapeutic measures, duration, outcome, patient satisfaction, and their interactions. The results show that the patients' satisfaction with the care received is very high and the pre-post effect sizes of inpatient treatment for depression are high.

Development and characterization of rat monoclonal antibodies to denatured mouse angiotensin-converting enzyme

Four new rat monoclonal antibodies, generated to denatured mouse somatic angiotensin-converting enzyme (ACE, CD143), detect mouse ACE with high sensitivity in Western blotting. Epitope mapping for the monoclonal antibodies--B12, 4G6 and 5C4--was also performed. Two monoclonal antibodies--B12 and 5C4--are directed to various epitopes on the N-domain--i.e., they recognized only the somatic isoform of mouse ACE. The monoclonal antibody H7 recognized an epitope on the C-domain of mouse ACE. The monoclonal antibody 4G6 was directed to a sequence on the N-domain of mouse ACE, which is homologous to a region of the C-domain and, as a result, also recognizes mouse testicular ACE (tACE) by means of Western blotting. In paraffin-embedded mouse tissues, all monoclonal antibodies detected all known expression sites of somatic ACE (sACE), e.g., the epithelial cells of the kidney proximal tubules, intestine and epididymis, and heterogeneously in endothelial cells. The monoclonal antibodies 4G6 and H7 additionally stained mouse tACE in spermatozoa and in mature spermatids. The monoclonal antibody 4G6 also demonstrated cross-reactivity with sACE from a broad spectrum of animal species, including human, rat, rabbit and bovine. However, this monoclonal antibody did not recognize the testicular isoform of ACE of these species. This set of monoclonal antibodies is useful for identifying even subtle changes in mouse ACE conformation because of denaturation. These monoclonal antibodies are also sensitive tools for the detection of mouse ACE in biological fluids and tissues by using proteomics approaches. Their high reactivity in paraffin-embedded tissues opens up opportunities to study possible changes in the pattern of ACE expression in knockout mouse models and may prove useful for correlating ACE expression in these models with human diseases.

High volume centers for esophagectomy: what is the number needed to achieve low postoperative mortality?

Aimed at reducing surgical deaths, several initiatives have attempted to establish volume-based referral strategies in high risk surgery. The detailed analysis of the literature of the last 10 years, comprising 13 papers on esophageal cancer, shows a clear reduction in postoperative mortality with increasing case volumes per year. Single papers have analyzed the main reasons for this phenomenon and showed that postoperative complication rates are lower in high-volume hospitals and management of complications is more successful. Further, long-term prognosis is also correlated to case-volume. In conclusion, the analysis shows that only with the experience of more than 20 esophagectomies per year can a significant reduction of the mortality, down to 4.9%, be achieved. Based on this survey, surgery of esophageal cancer is a task for high-volume hospitals because of decreased postoperative mortality and improved long-term prognosis compared with low volume hospitals.