Marcus Hudec

Detection of EpCAM positive and negative circulating tumor cells in metastatic breast cancer patients

Abstract Background. Immunomagnetic EpCAM based methods are used to enrich circulating tumor cells (CTCs) in metastatic breast cancer (mBC) patients. EpCAM negative CTCs may be missed. We addressed the question of the reliability of an EpCAM dependent assay to enrich CTCs. Methods. To elucidate this issue, our study has been designed to assess two different CTC enrichment technologies (i) in EpCAM positive (+) and EpCAM negative cell lines and (ii) in mBC patients in dependency on their respective EpCAM expression. These two technologies encompass one anti-EpCAM immunomagnetic enrichment technology, MACS HEA MicroBeads® (MACS), and one EpCAM independent density centrifugation method, OncoQuick® plus (OQ+). Furthermore, the coherence between EpCAM expression in the primary tumor tissue of mBC patients and the CTC detection rates in the corresponding patients is analyzed. Results. (i) MACS recovered significantly more EpCAM (+) than EpCAM (−) tumor cells (p < 0.001) in spiked blood samples. With OQ+ no significantly different recovery rates between EpCAM (+) and EpCAM (−) tumor cells (p = 0.796) were detected. (ii) In mBC patients MACS yielded a significantly higher (p = 0.024) detection rate of EpCAM (+) CTCs. No statistically significant difference (p = 0.070) was found concerning the EpCAM status-based detection rate of CTCs by OQ+. (iii) CTC detection rates are independent of the primary tumors’ EpCAM expression. Conclusions. EpCAM (−) CTCs can not be detected by immunomagnetic EpCAM dependent enrichment methods. EpCAM independent enrichment technologies seem to be superior to detect the entire CTC population. Evaluation of CTCs as prognostic marker should compromise EpCAM (+) and (−) subpopulations.

The prognostic relevance of various factors at the time of the first admission of the patient: Retrospective DÖSAK study on carcinoma of the oral cavity

In a retrospective study, on a sample of 1021 patients with carcinoma of the lips, oral cavity and oropharynx, the clinically available factors at the time of the patients first admission are analysed with reference to their prognostic relevance. Prognostically relevant factors are determined by both univariate and multivariate analyses. Of the 18 factors analysed, the following seven finally proved to be prognostically relevant: tumour size, degree of infiltration, degree of histological differentiation and site by organ of the primary tumour, the combination of evidence + clinical appearance + degree of fixation of the regional lymph nodes, age of the patient, and evidence of distant metastases. On the basis of these results it will be possible to create a prognostic index. This prognostic index should be eligible for use in clinical practice, as opposed to usual classification models.

Risk factors for severe bacterial infections after valve replacement and aortocoronary bypass operations: analysis of 246 cases by logistic regression

Risk factors for severe bacterial infections, that is, deep sternal wound infection, pneumonia, septicemia, and prosthetic valve endocarditis, were evaluated in 246 consecutive patients undergoing valve replacement (N = 84) or aortocoronary bypass operation (N = 162). Multiple logistic regression analysis was applied to determine the ability of putative risk factors to predict infection. The risk factors considered were age, sex, diabetes mellitus, duration of cardiopulmonary bypass (CPB), duration of operation, amount of blood restored on the day of operation, repeat thoracotomy for bleeding, intraaortic balloon pumping, reoperation, emergency operation, and the professional status of the surgeon. Severe infections occurred in similar frequency after valve replacement (8/84; 9.5%) and aortocoronary bypass (11/162; 6.8%). For patients who had a bypass procedure, repeat thoracotomy was the only factor significantly associated with infection (p = 0.0004). However, the classification analysis revealed that this variable alone is too unspecific for a reliable prediction. Univariate analysis indicated that restoration of more than 2,500 ml of blood (p = 0.0001), reoperation (p = 0.0821), duration of operation (p = 0.0061), duration of CPB (p = 0.0318), and intraaortic balloon pumping (p = 0.0281) were associated with infection following valve replacement. A model with three variables emerged from the multiple logistic regression: after correction for blood restoration, reoperation, and duration of CPB, no other variable was of additional predictive value. For patients who underwent valve replacement, the model performed well in predicting complications. The classification analysis revealed a high correspondence between observed and predicted instances of infection: it correctly predicted 75% of the patients with infection and 96% of those without infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Retrospective DÖSAK study on carcinomas of the oral cavity: Results and consequences***

In a multicentre, retrospective observational study on carcinomas of the oral cavity, including the lips and oropharynx, data material of 1021 patients has been analysed. The specific goals of this study were: Review of existing proposals for classification. Analysis of prognostically relevant factors of the tumour disease. Construction of a prognostic index for the determination of individual and collective prognoses. The following results were achieved: ad 1: All existing TNM-Classifications of oral cavity carcinomas so far fail to meet the requirements of the necessary criteria. ad 2: The multivariate analyses of prognostically relevant factors were performed with and without taking therapeutic factors into account. The results show unequivocally that reliable prognoses are only possible if various treatment modalities are considered. ad 3: This led to the construction of the treatment-dependent prognostic index TPI, which will be eligible for use in clinical-therapeutic cancer research and in clinical practice.

Docetaxel/cisplatin as first-line chemotherapy in patients with head and neck carcinoma: a phase II trial.

The objective of this Phase II study was to assess the clinical activity and toxicity of docetaxel (D) and cisplatin (P) in patients with locally advanced unresectable, metastatic, or recurrent squamous cell carcinoma of the head and neck (SCCHN).

Circulating tumor cells in metastatic colorectal cancer: Efficacy and feasibility of different enrichment methods

Comprehensive in vitro and in vivo studies comparing EpCAM-based methods with other cytometric CTC enrichment technologies in metastatic colorectal cancer (mCRC) patients are lacking. We compare four manual cytometric methods to detect CTCs in vitro and in mCRC patients. The EpCAM-based technology, MACS HEA MicroBeads((R)), showed a significant better tumor cell recovery rate compared to other cytometric methods (p-value<0.0001). CTCs of 38 mCRC patients were enriched with MACS HEA MicroBeads(R). Progression-free survival did significantly differ between mCRC patients without detectable and with >or= 1 CTCs (p=0.007). CTC enrichment with EpCAM coupled antibodies is superior to other cytometric methods and is a feasible method for CTC detection in mCRC patients.

Growing clinical evidence for the interaction of the p53 genotype and response to induction chemotherapy in advanced non–small cell lung cancer

OBJECTIVE The objective of this study is to establish clinical evidence that the p53 genotype can serve as a predictive marker for response to cisplatin-based induction therapy. METHODS Patients with advanced non-small cell lung cancer who had received neoadjuvant chemotherapy in the context of a prospective phase II trial were analyzed for the p53 genotype of their tumors. Response to induction therapy was then correlated to the p53 genotype as assessed by complete direct DNA sequencing. Patients had received 3 cycles of cisplatin and etoposide, and 1 cycle of simultaneous radiochemotherapy. All 3 treatment components mediate their cytotoxic effect through induction of apoptosis, which is suggested to require an intact p53 gene. In addition, the results from a previously published hypothesis-finding study are updated to demonstrate the consistency of clinical results and summarize currently available clinical evidence. RESULTS In the phase II trial, 35 patients underwent resection after induction chemotherapy, allowing a pathohistologic response assessment. The presence of a mutant p53 genotype was highly indicative of resistance to induction chemotherapy (P < .002). The sensitivity of a mutant p53 genotype to identify nonresponders was 94% (71.3-99.9 confidence interval). A normal p53 gene was significantly associated with radical resection (P < .004) and survival advantage (P = .02). CONCLUSION This is the second clinical evaluation demonstrating a significant relation between p53 genotype and response to induction therapy in non-small cell lung cancer. We conclude that the p53 genotype should be evaluated as a predictive marker for response to induction therapy in prospective randomized protocols.

Ontology-Based Generation of Bayesian Networks

Bayesian networks are indispensable for determining the probability of events which are influenced by various components. Bayesian probabilities encode degrees of belief about certain events and a dynamic knowledge body is used to strengthen, update, or weaken these assumptions. The creation of Bayesian networks requires at least three challenging tasks: (i) the determination of relevant influence factors, (ii) the determination of relationships between the identified influence factors, and (iii) the calculation of the conditional probability tables for each node in the Bayesian network.Based on existing domain ontologies, we propose a method for the ontology-based generation of Bayesian networks. The ontology is used to provide the necessary knowledge about relevant influence factors, their relationships, their weights, and the scale which represents potential states of the identified influence factors.The developed method enables, based on existing ontologies, the semi-automatic generation and alternation of Bayesian networks.

Octreotide combined with goserelin in the therapy of advanced pancreatic cancer-results of a pilot study and review of the literature

The two hormone analogues octreotide and goserelin have been shown to decelerate growth of human pancreatic cancer in vitro and in vivo. The objective of this pilot study was to investigate the efficacy and toxicity of the combination of these two agents in patients with advanced pancreatic cancer. Octreotide was injected subcutaneously in dosages increasing weekly, starting with 50 μg twice daily, until the level of maintenance therapy of 500 μg three times a day was reached. In addition, 3.8 mg goserelin acetate was administered subcutaneously at monthly intervals. A median of 7 cycles (range 1–27 cycles) were applied; 13 out of 14 patients entered into the study were evaluable for response and all 14 were evaluated for toxicity. In one patient with initially non-resectable pancreatic cancer, systemic therapy yielded a partial remission lasting 9 months. The degree of tumour regression then allowed a consecutive macroscopic radical tumour resection followed by an additional 6 months of no evidence of disease while the same drug combination was continued. In an additional 9 patients, no change of disease was observed, in some cases for a remarkably long time (up to 27 months). Nevertheless, the objective response rate of 7% (95% confidence interval 0±21%) was low. In 5 patients a clear improvement in their performance status was seen soon after the start of therapy; 3 patients showed progression of the disease at first evaluation or earlier and 1 patient was not evaluable at the time of study assessment. According to the product-limit method of Kaplan and Meier, the time to progression was 3.0±1.8 months [median±asymptotic standard error (ASE)] and overall survival was 6.0±1.5 months (median±ASE). Toxicity was rare and only of mild to moderate degree. Overall, the regimen under investigation did not meet the criteria for sufficient antitumoural effectiveness. Nevertheless, this study reinforces the concept that pancreatic cancer is principally responsive to endocrine therapy and therefore the further investigation of hormonal manipulation seems worth while in the future.

Early Prediction of Deep Sternal Wound Infection after Heart Operations by Alpha-1 Acid Glycoprotein and C-reactive Protein Measurements

Serum C-reactive protein (CRP) and alpha 1-acid glycoprotein (AAG) levels were studied in 188 patients undergoing heart operations with cardiopulmonary bypass. Mediastinitis or osteomyelitis of the sternum or both developed in 10 patients on postoperative day 4 to 13 (median, day 9). The mean CRP levels on day 2 were lower in patients with later deep sternal wound infection (9.1 +/- 1.5 mg/dl [mean +/- standard error]) compared with patients without major infections (14.0 +/- 0.8 mg/dl; p = 0.103 [univariate logistic regression]). AAG levels on day 2 reacted in a similar manner, yielding 78.2 +/- 5.5 mg/dl and 100.9 +/- 2.7 mg/dl, respectively (p = 0.0004). No correlation was found between CRP or AAG and duration of cardiopulmonary bypass, number of blood transfusions, or total protein levels on day 2. The white blood cell count (WBC) on day 2 was 13.1 +/- 1.7 X 10(3)/microliter for patients with infection and 9.7 +/- 0.3 for those without infection. Multivariate logistic regression analysis revealed that AAG, WBC, and CRP on day 2 were significant risk factors sufficiently predicting the probability of a deep sternal infection. After adjustment for these three variables, other variables (age, sex, total protein on day 2, diabetes mellitus, type of operation, duration of cardiopulmonary bypass, length of operation, repeat thoracotomy for bleeding, number of blood transfusions on the day of operation, intraaortic balloon pumping, reoperation, emergency operation, and surgeons professional status) were not of additional significance. The goodness of fit of the statistical model was confirmed by a high correspondence between predicted and observed cases of deep sternal infection.(ABSTRACT TRUNCATED AT 250 WORDS)