Expression of endogenous lectins (galectins, receptors for ABH-epitopes) and the MIB-1 antigen in esophageal carcinomas and their syntactic structure analysis in relation to post-surgical tumor stage and lymph node involvement

Squamous cell carcinomas of the esophagus, a disease with poor prognosis, are especially frequent in China and South Africa. To initiate the study of endogenous lectins in this tumor class we employed synthetic neoglycoconjugates and focused on galectins as markers. Histological sections of 43 cases of esophageal carcinomas were analyzed with labeled galectins-1 and -3 and their specific antibodies, neoglycoconjugates exposing chemically prepared histo-blood group A-, B- and H-trisaccharides and the antibody MIB-1 (Ki-67). Features of structural and numerical staining intensities determined quantitatively were correlated to clinical data sets of pTN stages, sex and age of patients. Low tumor stages (pT1/T2) were seen in 10/43 cases (23%) and 65% of the carcinomas surgically treated lacked notable lymph node involvement (pN0). The women were younger than the men (47 years versus 54 years). The proliferation activity of the tumor cells was high and amounted to 75% at average. The presence of galectin-1 and the structural entropy of distribution of staining with carrier-immobilized A-trisaccharide were associated with pN stages. These initial data indicate that distinct glycohistochemical features appear to have prognostic significance in this tumor class, adding to the emerging significance of this marker class in lung cancer.

Relevance of N-acetyltransferase 1 and 2 (NAT1, NAT2) genetic polymorphisms in non-small cell lung cancer susceptibility

The highly polymorphic N-acetyltransferases (NAT1 and NAT2) are involved in both activation and inactivation reactions of numerous carcinogens, such as tobacco derived aromatic amines. The potential effect of the NAT genotypes in individual susceptibility to lung cancer was examined in a hospital based case-control study consisting of 392 Caucasian lung cancer patients [152 adenocarcinomas, 173 squamous cell carcinomas (SCC) and 67 other primary lung tumours] and 351 controls. In addition to the wild-type allele NAT1*4, seven variant NAT1 alleles (NAT1*3, *10, *11, *14, *15, *17 and *22) were analysed. A new method based on the LightCycler (Roche Diagnostics Inc.) technology was applied for the detection of the polymorphic NAT1 sites at nt 1088 and nt 1095. The NAT2 polymorphic sites at nt 481, 590, 803 and 857 were detected by polymerase chain reaction-restriction fragment length polymorphism or LightCycler. Multivariate logistic regression analyses were performed taking into account levels of smoking, age, gender and occupational exposure. An increased risk for adenocarcinoma among the NAT1 putative fast acetylators [odds ratio (OR) 1.92 (1.16-3.16)] was found but could not be detected for SCC or the total case group. NAT2 genotypes alone appeared not to modify individual lung cancer risk, however, individuals with combined NAT1 fast and NAT2 slow genotype had significantly elevated adenocarcinoma risk [OR 2.22 (1.03-4.81)] compared to persons with other genotype combinations. These data clearly show the importance of separating different histological lung tumour subtypes in studies on genetic susceptibility factors and implicate the NAT1*10 allele as a risk factor for adenocarcinoma.

[Benign, pulmonary metastatic leiomyoma of the uterus]

Pulmonary nodules resected in 10 patients were histologically classified as benign metastatic leiomyoma of the uterus. Hysterectomy because of myoma had been performed between 0 and 24 years earlier (median 14.9 years). Between 1 and 27 nodules were found in one or both lungs. Patients presenting with a single nodule had it resected with diagnostic intent and were followed up. Multiple nodules were resected if the loss of parenchyma was tolerable; otherwise, one lesion was resected for diagnosis. In some cases antihormonal therapy was performed postoperatively. The median duration of follow-up was 4.7 years. In this time, no local complication occurred, and no patient died of this disease. Apparently, benign metastatic leiomyoma of the uterus biologically shows benign behaviour. New manifestation or progressing growth of non-resected lesions does occur, however. Consequently, regular follow-up is required. Local complications indicate surgical intervention.

Telecommunication--a new tool for quality assurance and control in diagnostic pathology

Telepathology is the diagnostic work of a pathologist at a distance. It includes specific application fields which require specific system solutions. These comprise: a. frozen section service; b. expert consultations; c. remote control measurements, and d. education and training. Applications but, in addition, all aspects of diagnosis, especially those involved in the daily work flow of a pathologist. The image quality, transfer rates, and screen resolution of telepathology systems are sufficient for an additional or primary judgment of histological slides and cytological smears. It is, therefore, possible to include this technique into intralaboratory quality control of all steps of diagnostic procedures and to use this technique for quality assurance and control. Diagnostic quality is not a well defined term, and depends, in addition to external circumstances, on the diagnosis itself. The diagnostic quality can be maintained or even improved by use of telepathology systems. They can serve for control of image quality, access to various information sources, simultaneous transfer of images and diagnosis, and continuous education of the involved pathologists. For example, in continuous education and training, as a first step the pathologist should have access to an image data bank storing images related to the specific case, for example images taken from the same organ and from patients of similar age. The final stage would be an intra-diagnostic learning from the specific case; i.e. the time difference between questionnaires for a difficult diagnosis and the final diagnosis will become a minimum. Automated storing of the specific and diagnosis-associated images of the case will permit an open diagnostic system which will itself adjust to the micro-environment of the department of pathology. Although this future scenario has not been implemented to our knowledge, there is little doubt the development in telepathology will promote the technical procedures in the environment of a diagnostic pathologist. Telepathology is, therefore, not a substitute of conventional diagnostic procedures but a real improvement in the world of pathology.

Glyco- and immunohistochemical refinement of the differential diagnosis between mesothelioma and metastatic carcinoma and survival analysis of patients

The aim of this study was to analyse the diagnostic value of selected glyco- and immunohistochemical probes for discrimination between mesotheliomas and metastatic carcinomas within the pleura, and to evaluate prognostic indicators in the tested panel. A panel of nine markers (five antibodies, two neoglycoproteins, and labelled hyaluronic acid) was applied to a total of 264 specimens with mesotheliomas (118 cases) and metastatic carcinomas in the pleura (146 cases); the material consisted exclusively of surgical specimens. The diagnosis obtained by standard procedures was further substantiated through a detailed follow-up and clear-cut descriptions of primary sites. The metastatic tumours originated from the lung (82 cases), breast (47 cases), colon (three cases), and kidney (two cases); in 12 cases, however, the tumour origin could not be ascertained. In detail, the probes tested included antibodies against carcinoembryonic antigen (CEA), vimentin, calretinin, mesothelial cells (HBME-1), calcyclin and keratin-5; and also biotinylated neoglycoproteins with ganglioside GM1 and N-acetyl-D-glucosamine (GlcNAc) as the ligand part, and hyaluronic acid. Carrier-immobilized ganglioside GM1 and hyaluronic acid displayed the highest specificity and sensitivity for mesotheliomas, followed by calretinin and HBME-1, whereas keratin-5 and vimentin were of low specificity (43% and 52%, respectively). Metastatic carcinomas could be discerned by CEA detection and application of GlcNAc-bearing neoglycoprotein with similar sensitivity (76% and 72%, respectively) and specificity (91% and 86%, respectively). In cases of breast carcinoma, the maximum specificity (59%) and sensitivity (67%) were low for all markers. Patients with mesothelioma survived longer than those with metastatic carcinoma, especially those with detectable binding sites for hyaluronic acid. No association of tumour type and binding properties of the other applied probes with survival of the patients could be found at a statistically significant level. It is concluded that in routine practice, the application of carrier-immobilized GM1, hyaluronic acid, and antibodies against calretinin and HBME-1 is useful for confirmation of mesothelioma, whereas the detection of CEA and GlcNAc-specific binding sites is useful for distinguishing metastatic carcinoma from mesothelioma. Despite the rather infrequent occurrence of mesotheliomas in women, particular attention should be given to exclude or confirm metastatic breast carcinoma in cases of unknown history or long metastatic interval.

Endobronchial juvenile hemangioma--a case report of a neonate including immunohistochemical monitoring and nuclear, cellular, and vascular morphometry

A 3-month-old female child suffered from tachypnea and dyspnea with abnormal blood gas values. Chest X-rays revealed an increased transparency of the left lung and a mediastinal shift to the right side. High resolution computed tomography (CT) documented a narrowing of the left upper stem bronchus. Ensuing endoscopy detected an occlusive endobronchial tumor mass that did not infiltrate the bronchial cartilage as confirmed with endobronchial ultrasonic monitoring. Based on gross histological examination of the surgical specimen obtained using sleeve resection, the highly vascularized tumor exhibited an adenomatoid growth pattern with a rather homogeneous population of nuclei. The light microscopical presentation was consistent with a juvenile (infantile) hemangioma, which was confirmed using immunohistochemical examinations despite the display of neuroendocrine features. Although endobronchial juvenile hemangiomas are an extremely rare event in early childhood, this case underscores the necessity to not neglect its occurrence in differential diagnosis.

Stimulus characteristics within directives: effects on accuracy of task completion

Three experiments were conducted in an outpatient setting with young children who had been referred for treatment of noncompliant behavior and who had coexisting receptive language or receptive vocabulary difficulties. Experiment 1 studied differential responding of the participants to a brief hierarchical directive analysis (least-to-most complex stimulus prompts) to identify directives that functioned as discriminative stimuli for accurate responding. Experiment 1 identified distinct patterns of accurate responding relative to manipulation of directive stimulus characteristics. Experiment 2 demonstrated that directives identified as effective or ineffective in obtaining stimulus control of accurate responding during Experiment 1 continued to control accurate responding across play activities and academic tasks. Experiment 3 probed effects of the interaction between the type of directive (effective vs. ineffective) and the reinforcement contingency (differential reinforcement for attempts vs. differential reinforcement for accurate responses) on accurate task completion and disruptive behavior. Results suggested that behavioral escalation from inaccurate responding to disruptive behavior occurred only when ineffective directives were combined with differential reinforcement for accurate task completion. The overall results are discussed in terms of developing a methodology for identifying stimulus characteristics of directives that affect accurate responding.

hOGG1 polymorphism and loss of heterozygosity (LOH): significance for lung cancer susceptibility in a caucasian population

Oxidative damage is implicated in several chronic diseases including cancer. 8-Hydroxyguanine (8-oxoG) is one of the major promutagenic DNA lesions, which is produced by reactive oxygen species, causes G:C to T:A transversions and is excised by OGG1, an 8-oxoG specific DNA glycosylase/AP-Lyase. In a nested case-control study, gDNA from 105 Caucasian primary non-small cell lung cancer cases and 105 matched controls was screened for 6 possible new polymorphic sites in the human OGG1 gene, detected previously mainly in tumour tissue. The previously described Ser(326)Cys polymorphism was found to be common (allele frequency 0.22) in Caucasians. However, no major difference in Ser(326)Cys genotype distribution could be detected between cases and controls. Two 5;-end polymorphisms previously found in Japanese as well as Arg(131)Gln could not be detected in this population. An Ala(85)Ser polymorphism was found in 2 controls, whereas Arg(46)Gln was detected in only 1 case. As the hOGG1 gene is mapped (3p26.2) to a region frequently lost in primary lung tumours, the frequency of loss of heterozygosity (LOH) was investigated. Forty-three percent of the studied lung tumours exhibited loss of one of the hOGG1 alleles. The wt Ser(326) allele was not predominantly lost in our sample set, which suggests a minor role of this polymorphism in tumourgenesis. Our results show that LOH at the hOGG1 gene locus is a very common occurrence in lung tumourgenesis, possibly leading to increased mutational damage due to ROS in smokers. However, the hOGG1 polymorphisms studied are probably not major contributors to individual lung cancer susceptibility in Caucasians.

hOGG1 polymorphism and loss of heterozygosity (LOH): significance for lung cancer susceptibility in a caucasian population

Oxidative damage is implicated in several chronic diseases including cancer. 8-Hydroxyguanine (8-oxoG) is one of the major promutagenic DNA lesions, which is produced by reactive oxygen species, causes G:C to T:A transversions and is excised by OGG1, an 8-oxoG specific DNA glycosylase/AP-Lyase. In a nested case-control study, gDNA from 105 Caucasian primary non-small cell lung cancer cases and 105 matched controls was screened for 6 possible new polymorphic sites in the human OGG1 gene, detected previously mainly in tumour tissue. The previously described Ser(326)Cys polymorphism was found to be common (allele frequency 0.22) in Caucasians. However, no major difference in Ser(326)Cys genotype distribution could be detected between cases and controls. Two 5;-end polymorphisms previously found in Japanese as well as Arg(131)Gln could not be detected in this population. An Ala(85)Ser polymorphism was found in 2 controls, whereas Arg(46)Gln was detected in only 1 case. As the hOGG1 gene is mapped (3p26.2) to a region frequently lost in primary lung tumours, the frequency of loss of heterozygosity (LOH) was investigated. Forty-three percent of the studied lung tumours exhibited loss of one of the hOGG1 alleles. The wt Ser(326) allele was not predominantly lost in our sample set, which suggests a minor role of this polymorphism in tumourgenesis. Our results show that LOH at the hOGG1 gene locus is a very common occurrence in lung tumourgenesis, possibly leading to increased mutational damage due to ROS in smokers. However, the hOGG1 polymorphisms studied are probably not major contributors to individual lung cancer susceptibility in Caucasians.

Cathepsin B in infiltrated lymph nodes is of prognostic significance for patients with nonsmall cell lung carcinoma

BACKGROUND

Tumor cells require specific proteolytic enzymes for invasion and metastasis, including lysosomal peptidases--cathepsins. Cathepsin B is a lysosomal cysteine peptidase, which appears to play a major role in invasion and metastasis of human tumors. In this study, the authors focused on the possible role of cathepsin B in lymphogenic metastasis by investigating the enzyme localization and its activity in lung tumors and corresponding tumor-infiltrated lymph nodes.

METHODS

Cathepsin B activity was determined in lung tumors, lung parenchyma, and tumor cell-infiltrated and noninfiltrated regional lymph nodes of the same patient. The authors investigated 35 cancer patients suffering from nonsmall cell lung carcinoma. Cathepsin B throughout activity was measured by cleavage of the fluorogenic substrate Z-Arg-Arg-AMC at pH 6.0.

RESULTS

The median specific cathepsin B activity was highest in tumors, followed by the infiltrated lymph nodes, noninfiltrated lymph nodes, and lung parenchyma. The authors showed a significant 1.8-fold increase in cathepsin B activity in tumor-infiltrated lymph nodes compared with noninfiltrated regional lymph nodes and a 4.5-fold increase in lung tumor tissue compared with lung parenchyma. High cathepsin B activity, both in tumors and tumor cell-infiltrated lymph nodes, indicated poor prognosis for overall survival. Immunohistochemical analysis showed the presence of cathepsin B in histiocytes and tumor cells but not in lymphocytes of lymph node tissue.

CONCLUSIONS

The authors' findings on higher cathepsin B levels in tumor cell-infiltrated lymph nodes show that increased level of cathepsin B activity is characteristic of the invasive tumor cell phenotype. This corroborates the hypothesis, that tumor cell associated cathepsin B may play a role in lymphogenic metastasis. The authors' results support the use of lymph node associated cathepsin B as a prognostic factor for survival of patients with lung carcinoma.

Diffuse pulmonary hemosiderosis after exposure to pesticides. A case report

This report describes the clinical, radiological, microscopical and ligandohistochemical findings in a 17-year-old woman who suffered from an acute onset of pulmonary hemosiderosis after inhalation of pesticides used for the cultivation of strawberries. She complained of headache, dyspnea, rhinitis, weakness and recurrent severe hemoptysis. Chest radiographs revealed bilateral patchy infiltrates, predominantly in the lower parts of both lungs. The consecutive severe anemia was treated by multiple blood transfusions which were repeated every 4-5 days. Open lung biopsies displayed signs of diffuse hemorrhage with hemosiderin-loaded macrophages, some hyaline membranes, focal fibroid deposits with intermingled histiocytes, mild interstitial fibrosis and focal intra-alveolar calcified bodies surrounded by foreign body giant cells. Analysis of endogenous lectins failed to demonstrate expression of binding capacities for maltose, fucose, mannose, lactose and sialic acid, Neither binding capacities for the macrophage-migration-inhibitory factor nor its presence, as analyzed by labeled sarcolectin, could be detected histochemically. The light microscopical findings are consistent with a longer-lasting diffuse pulmonary hemosiderosis; the presence of calcified bodies and foreign body giant cells (including the ligandohistochemical data) argues for a causal role of inhaled substances. The patient's clinical course improved after cyclophosphamide treatment, which restored her ability to work and released her from the need for recurrent blood transfusions.

Routine DNA cytometry of benign and malignant pleural effusions by means of the remote quantitation server Euroquant: a prospective study

AIM

To analyse the practicability and potential assistance of static DNA cytometry performed by means of the remote quantitation server Euroquant and the internet in routine diagnostic analysis of pleural effusions, and to outline the role of DNA cytometry on pleural effusions in distinguishing between benign and malignant (and herein primary versus metastatic) effusions.

MATERIALS AND METHODS

Cytological smears of 294 pleural effusions were stained with the Feulgen method. The DNA content of a minimum of 300 randomly chosen analysis nuclei and 30 reference nuclei (lymphocytes) was measured by internet connection to the remote quantitation server Euroquant. Cytometric features were derived from the histograms, and the time needed for case evaluation, the reliability of staining and measurement procedures, and the contribution to the final diagnosis were evaluated.

RESULTS

Only 120 of 294 pleural effusions could be measured. The total measurement time for each specimen was 60 minutes. The guidelines of the consensus report on DNA measurements were fulfilled. Seventy eight malignant (18 mesotheliomas, 60 metastatic tumours) and 42 benign effusions were measured. Seven of 78 malignant effusions were euploid and none of 42 benign effusions were aneuploid. The sensitivity and specificity were 91% and 100%, respectively, for distinguishing benign from malignant effusions, and 95% and 100%, respectively, for discriminating between benign and malignant effusions caused by metastatic malignant tumours.

CONCLUSIONS

Static DNA cytometry using the remote quantitation server Euroquant can be performed reliably in the routine diagnosis of pleural effusions; however, only 40% of effusions meet the technical requirements for static DNA cytometry. Within the measurable cases, static DNA cytometry made an important contribution to the confirmation/exclusion of malignancy.

Integrated nuclear fluorescence and expression of hormone-binding sites in malignant pleural effusions

OBJECTIVE

To investigate potential disease- and prognosis-associated nuclear and cellular features from cell properties in a prospective study on malignant pleural effusions.

STUDY DESIGN

Integrated nuclear fluorescence and the expression of binding capacities of carrier-immobilized estradiol, progesterone and testosterone; and of labeled sarcolectin; and the presence of calcyclin were measured in 50 cases with proven malignant pleural effusions (10 mesotheliomas, 40 metastasizing tumors). A double fluorescence technique using the fluorochrome DAPI and a Texas Red-based avidin-biotin detection system were applied. Detailed clinical data, including the follow-up for up to 40 months, were included.

RESULTS

Pleural effusions in all patients with mesotheliomas occurred prior to (9/10) or at the time of histologic confirmation. Mesotheliomas had the highest tumor cell fraction (12.4%) in S phase and breast carcinomas the lowest (10.7%). More than 80% of malignant cells expressed binding capacities for the applied probes. A statistically significant correlation was noted between the S-phase-related tumor cell fraction and the expression of progesterone receptors. Survival was associated with tumor origin, treatment by pleurodesis, and certain cytometric and histochemical features.

CONCLUSION

The immunofluorescence double-staining technique can be applied successfully in malignant effusions to combine DNA measurements with those of immunohistochemical and ligand histochemical reactivity.

Benign metastasizing leiomyoma of the uterus: documentation of clinical, immunohistochemical and lectin-histochemical data of ten cases

The clinical histories of 10 women suffering from benign metastasizing leiomyoma (BML) after hysterectomy and information on lung lesions detected in these women are presented, together with corresponding data for 2 women with metastasizing leiomyosarcoma of the uterus for comparison: gross appearance, survival, and light microscopical, immunohistochemical and lectin-histochemical findings are reported. All patients with BML had undergone hysterectomy for uterus leiomyomatosus without any detection of sarcomatous lesions in the uterus wall. After a median period of 14.9 years intrapulmonary masses were detected by imaging techniques. On average, six nodules with a mean diameter of 1.8 cm were seen. Resection of the lesions was performed in all cases. The immunohistochemical and lectin-histochemical examination of the tumors included analysis of the proliferation-associated protein Ki-67, the p53 protein, estrogen and progesterone receptor, sarcolectin as an indicator of the presence of lymphokine macrophage migration inhibitory factor, antibodies and the labeled protein to assess galectin (galactoside-binding animal lectin)-dependent parameters, analysis of tumor vascularization (CD-34), and expression of bcl-2, vimentin, smooth muscle actin, desmin, and keratin. The lesions were characterized by low proliferation activity of 2.9% (measured with Ki-67), frequent hormone receptor expression (8 of the 10 cases presented hormone-specific receptors), low to moderate vascularization compared with metastases from the two uterine sarcomas, remarkable p53 overexpression and frequent expression of the lymphokine, the galectins and accessible binding sites. The median survival of the BML patients was 94 months after excision of the intrapulmonary lesions, and the maximum survival of the two sarcoma patients was 22 months. The results recorded in this patient sample with the methodology applied suggest that benign metastasizing leiomyomas are a slow-growing variant of leiomyosarcoma of the uterus, which becomes clinically apparent at a young age and progresses with low velocity.

Association of concentration of asbestos and asbestos-like fibers with the patient's survival and the binding capacity of lung parenchyma to galectin-1 and natural alpha-galactoside- and alpha-mannoside-binding immunoglobulin G subfractions from human serum

Our aim in this study was to search for lung parenchyma alterations associated with asbestos and/or asbestos-like fiber concentration. This was done by means of immuno- or glycohistochemistry. The hot-ashing technique determined the asbestos and asbestos-like fiber concentrations in the lung tissues of 100 patients of whom 52 were treated for primary lung and 25 for secondary lung tumors; fiber concentration was also measured for 23 patients whose disease was benign. The results were correlated to smoking habits, survival of the patients, and expression of binding capacities for endogenous lectins, natural carbohydrate-binding and lectin-specific antibodies. The cohort with proven asbestos exposure revealed a mean fiber concentration 114 f/g compared to 95 f/g in the non-exposed group. An increased asbestos fiber concentration was correlated to galectin-1-binding and the presence of epitopes for natural immunoglobulin G subfractions with selectivity to alpha-galactosides and alpha-mannosides. The survival of patients with primary and secondary lung tumors was negatively associated with the fiber concentration. The data indicate that increased presence of asbestos is correlated with an alteration of defined glycohistochemical features of alveolar lining cells.

Diagnostic errors in interactive telepathology

Telepathology (TP) as a service in pathology at a distance is now widely used. It is integrated in the daily workflow of numerous pathologists. Meanwhile, in Germany 15 departments of pathology are using the telepathology technique for frozen section service; however, a common recognised quality standard in diagnostic accuracy is still missing. In a first step, the working group Aurich uses a TP system for frozen section service in order to analyse the frequency and sources of errors in TP frozen section diagnoses for evaluating the quality of frozen section slides, the important components of image quality and their influences an diagnostic accuracy. The authors point to the necessity of an optimal training program for all participants in this service in order to reduce the risk of diagnostic errors. In addition, there is need for optimal cooperation of all partners involved in TP service.

Telediagnosis of transbronchial fine needle aspirations--a feasibility study

AIM

To analyze the diagnostic accuracy of telediagnostic procedures for transbronchial fine needle aspirations.

MATERIAL AND METHODS

A double blind study was performed on cytological slides of 54 randomly selected cases with transbronchial fine needle aspirations. The slides were digitized using a Leica digital camera DC100 mounted on a microscope Leica Laborlux S, and analyzed by an experienced pathologist without knowing the definite diagnosis or any additional clinical data. The diagnoses stated by analyzing the digital images were compared to the final conventional diagnoses. In addition, the duration of the digital diagnosis, used magnifications, and difficulties for correct sampling were documented.

RESULTS

The "digital" diagnoses of the 54 cases were all in general agreement with the definite diagnoses. No wrong positive or wrong negative case in respect to malignant/non-malignant (31/23) or to small cell/non-small cell (9/22) occurred. The performance of a digital diagnosis lasted for 115 s at average (15-260 s), and is significantly longer compared to that of conventional fine needle aspiration judgement (20 s). The screening magnification was commonly set to x2.5, that for definite diagnostic analysis x40. Benign diseases (2 tuberculosis and 3 sarcoidosis cases) were correctly classified.

CONCLUSIONS

Telepathology systems can probably be used for fine needle aspiration analysis without major diagnostic errors. Their use can improve the endoscopic sampling and avoid second anesthesia when missing the lesion of request during the first examination.

Recent developments and present status of telepathology

Telepathology which is the diagnostic work of a pathologist at a distance has been developed to routine application within the last ten years. It can be classified in relation to application, technical solutions, or performance conditions. Diagnostic pathology performance distinguishes primary diagnosis (for example, frozen section statement) from secondary diagnosis (for example, expert consultation) and quality assurance (diagnostic accuracy, continuous education and training). Applications comprise (a) frozen section service; (b) expert consultations; (c) remote control measurements; and (d) education and training. The technical solutions distinguish active (remote control, live imaging) systems from passive (conventional microscope handling, static imaging), and the performance systems with interactive (on-line, live imaging) use from those with passive (offline, static imaging) practice. Intra-operative frozen section service is mainly performed with remote control systems; whereas expert consultations and education/training are commonly based upon Internet connections with static imaging in an off-line mode. The image quality, transfer rates, and screen resolution of active and passive telepathology systems are sufficient for an additional or primary judgment of histological slides and cytological smears. From the technical point of view, remote control telepathology requires a fast transfer and at least near on-line judgement of images, i.e., image acquisition, transfer and presentation can be considered one performance function. Thus, image size, line transfer rate and screen resolution define the practicability of the system. In expert consultation, the pixel resolution of images and natural color presentation are the main factors for diagnostic support, whereas the line transfer rate is of minor importance. These conditions define the technical compartments, especially size and resolution of camera and screen. The performance of commercially available systems has reached a high quality standard. Pathologists can be trained in a short time and use the systems in a routine manner. Several telepathology systems have been implemented in large Institutes of Pathology which serve for frozen section diagnosis in small hospitals located in the local area. In contrast, expert consultation is mainly performed with international connections. There is a remarkable increase of expert consultations by telepathology according to the experiences of the Armed Forces Institute of Pathology or the Department of Pathology, Thoraxklinik, Heidelberg. In expansion of these experiences, a "globalization" of telepathology can be expected. Telepathology can be used to shrink the period necessary for final diagnosis by request for diagnostic assistance to colleagues working in appropriate related time zones. Telepathology is, therefore, not a substitute of conventional diagnostic procedures but a real improvement in the world of pathology.

Immunochemical analysis of cathepsin B in lung tumours: an independent prognostic factor for squamous cell carcinoma patients

In order to evaluate the possible role of the proteolytic enzyme cathepsin B (cath B) in human non-small cell lung cancer (NSCLC) we examined cath B concentrations (cath B(C)) and activities (cath B(A)) in homogenates of 127 pairs of lung tumour tissues and corresponding non-tumourous lung parenchyma. Total cath B activity (cath B(AT)) and enzymatic activity of the fraction of cath B, which is stable and active at pH 7.5 (cath B(A7.5)) were determined by a fluorogenic assay using synthetic substrate Z-Arg-Arg-AMC. The immunostaining pattern of cath B was determined in 239 lung tumour tissue sections, showing the presence of the enzyme in tumour cells (cath B(T-I)) and in tumour-associated histiocytes (cath B(H-I)). The median levels of cath B(AT), cath B(A7.5) and cath B(C) were 5.6-, 3.2- and 9.1-fold higher (P < 0.001), respectively, in tumour tissue than in non-tumourous lung parenchyma. Out of 131 tissue sections from patients with squamous cell carcinoma (SCC), 59.5% immunostained positively for cath B, while among the 108 adenocarcinoma (AC) patients 48.2% of tumours showed a positive reaction. There was a strong relationship between the levels of cath B(AT), cath B(A7.5), cath B(C) and cath B(T-I) in the primary tumours and the presence of lymph node metastases. Significant correlation with overall survival was observed for cath B(T-I) and cath B(A7.5) (P < 0.01 and P < 0.05, respectively) in patients suffering from SCC. In these patients positive cath B in tumour cells (cath B(T-I)) and negative cath B in histiocytes (cath B(H-I)) indicated significantly shorter survival rate compared with patients with negative cath B(T-I) and positive cath B(H-I) (P < 0.0001). In contrast, in AC patients, both, positive cath B(T-I) and positive cath B(H-I), indicated poor survival probability (P < 0.014). From these results we conclude that the proteolytic enzyme cath B is an independent prognostic factor for overall survival of patients suffering from SCC of the lung.

Evaluation of histochemical anthracyclin binding as potential prognostic parameter in small cell lung cancer

In the quest to define further prognostic indicators for small cell lung cancer we have combined standard prognostic evaluation of several tissue and serum markers with monitoring the capacity of tumor cells to bind a carrier-immobilized anthracyclin at the time of diagnosis. The prospective study on 150 patients with small cell lung cancer (SCLC) was performed including the performance of immunohistochemical analysis [neuron-specific enolase (NSE), keratin, and vimentin], and serum marker measurements [NSE, carcinoembryonic antigen (CEA), and CYFRA], flanked by compilation of data on clinical staging at the time of diagnosis, cytostatic drug regimen, remission rates, and survival of the patients. As innovative test substance we synthesized and histochemically exploited carrier-immobilized doxorubicin. The cohort includes 108 men and 42 women grouped into stage I (limited disease: 69 patients; median survival: 317 days), stage IIa (extensive disease IIa: 19 patients; median survival: 244 days), and stage IIb (extensive disease IIb: 62 patients; median survival: 202 days). An oat-cell type was diagnosed in 112 patients, an intermediate cell type in 32 patients, and a combined cell type in 6 patients. Immunohistochemically, 123 tumors (82%) were positive for NSE, 75 tumors (50%) positive for keratin, and 26 tumors (18%) positive for vimentin. In 101 tumors (67%) specific intracellular binding of doxorubicin could be detected. Elevated serum levels for CEA and NSE were associated with an unfavorable prognosis of the corresponding patients (CEA, 261 days vs 467 days; NSE, 316 days vs 414 days). 137 patients received chemotherapy (median survival: 356 days) and 13 patients were not treated (median survival: 119 days). The six patients with the combined cell type and other patients with negative tumor specimen concerning the capacity to bind the anthracyclin were subject of a significantly shortened survival period irrespective of the cytostatic regimen (277 days vs. 381 days). Despite the current uncertainty of the biochemical nature of the histochemically detectable binding, the technical feasibility of the given interdisciplinary approach encourages to further pursue the documentation of anthracyclin binding.

Galectins-1 and -3 and their ligands in tumor biology. Non-uniform properties in cell-surface presentation and modulation of adhesion to matrix glycoproteins for various tumor cell lines, in biodistribution of free and liposome-bound galectins and in their expression by breast and colorectal carcinomas with/without metastatic propensity

Protein (lectin)-carbohydrate (cellular glycoconjugate) recognition is operative in biochemical information transfer. Galectins constitute a family of endogenous galactoside-binding lectins with conserved features in the binding site. The members of this lectin category are assumed to be involved in cell adhesion and growth regulation. To assess to what extent the different modes of binding-site presentation and/or carbohydrate fine-specificities will affect aspects of galectin behavior, homodimeric cross-linking galectin-1 and monomeric chimeric galectin-3, with its collagenase-sensitive stalk linked to the carbohydrate-recognition domain, were investigated. Cell-surface expression of the two galectins and accessible galectin-binding sites on various tumor cell lines was ascertained by FACScan analysis. In particular, ligand accessibility for the two galectins differed for the tested cell line types. Binding of tumor cells to laminin and plasma or placental fibronectin was generally reduced by treatment of cells or matrix with galectins. Galectin-3 was more efficient than galectin 1 at impairing laminin's potency as matrix. Cell binding of galectin-1, on the other hand, proved on average more effective for blocking cell association to fibronectins after its preincubation with cell suspensions. Differences were also apparent in the biodistribution of the galectins, where an avian homolog of galectin- served as the control to distinguish effects of spatial and sugar-binding features. Histopathological analysis of lymph-node-negative and -positive breast and colorectal carcinomas (n = 180 including 60 metastatic lesions) indicated a correlation of either increased galectin-1 binding and reduced galectin-3 expression or reduced binding of both galectins with the occurrence of lymph node lesions. Together with data on the heparin-binding lectin, revealing reduced expression to be associated with a positive lymph-node status in the breast cancer group, these results can be interpreted to reflect cell-type-dependent requirements of galectin ligand presentation during the metastatic cascade. By introducing mammalian lectins to lectin-histochemical studies, the detection of quantitative differences in glycosylation brings an understanding of its cell biological significance one step closer.

Basic aspects of and recent developments in telepathology in Europe, with specific emphasis on quality assurance

Telepathology is the diagnostic work of a pathologist from a distance and includes all specific fields of diagnostic pathology, such as frozen section services, expert consultation, cytometric and histometric measurement, and continuous education. For about 15 years experience has been collected at several universities in the United States and Europe based upon analog telephone lines (9.2 kbaud), digitized lines (ISDN, 64 kbaud), broad band connections (1.5 Mbaud) and the World Wide Web (28 kbaud). Potential use can be expected in the application of telepresentation, remote slide preparation, remote central diagnostics and telediscussion. The transfer of still images is well developed; that of live images is used in only a few institutions for frozen section services. The image quality and spatial resolution as well as the transfer speed are sufficient for expert consultations, morphometric measurements, quality assurance and education. All applications focus on discontinuous work flow. Although the European Community focuses on user needs and standardization aspects of telepathology by sponsoring a widespread telepathology project (Europath), implementation of telepathology into routine application in the continuous work flow has still to be developed. The technical equipment has still to be adjusted to the labor flow charts in routine pathologic diagnostic procedures. Telepathology seems to be the appropriate technique to offer both improvement in diagnostic quality and inclusion of the "control institution" into diagnostic responsibility.

The application of thermodynamic principles to histochemical and morphometric tissue research: principles and practical outline with focus on the glycosciences

Physicochemical terms such as entropy or current of entropy are commonly used to refer solely to the description of reactions in the realm of chemistry and physics. Since these thermodynamic terms have a predictive value for the further course of development of such reactions, e.g., extent of a chemical reaction or affinity of molecular interactions, it is tempting to introduce the respective algorithms to biological problems. By combining quantitative morphology with the histochemical visualization of distinct cellular and textural properties such as nuclear DNA contents or intensity of histochemical staining, equations from the general theory of thermodynamics can be adapted. They permit appropriate calculations to be performed which introduce the entropy concept to the processing of the information collected by analysis of structures formed by histochemically labeling cells. The theory of weighted graphs offers the appropriate mathematical tools. Nuclei are defined as vertices. Their DNA contents measured by the integrated optical density or additional cellular features (for example staining intensity of applied immuno-/ligandohistochemical probes) define the associated weights and the minimum spanning tree as a derivative from Voronoi's theorem for the definition of the geometrical neighborhood. This technique is equivalent to syntactic structure analysis as developed by Lu and Fu (1978), Sanfeliu et al. (1981), Kayser and Schlegel (1982), and Kayser (1988). Assuming that the texture of a healthy tissue is displayed in the energetically most efficient and stable manner to perform the required biological functions, i.e., to maintain the lowest level of entropy, deviations from this level are reflected in differences in distances and weights between neighboring nuclei or cells. The measure of textural differences in relation to the normal appearance of an organ or tissue is denoted as structural entropy. Since organisms or their compartments are thermodynamically open systems, they are insufficiently described by the (structural) entropy. This parameter only provides a snapshot, with no information about the status of entropy changes from a directed exchange with the environment. The current of entropy, which is equivalent to the amount of entropy exported or imported through a boundary, is an appropriate measure of the "thermodynamic distance" of the system under consideration from its environment, as is readily appreciated for tumors. A solid tumor is a biological system embedded in another one (healthy tissue). Its current of entropy can be calculated if its boundary and proliferative activity are known. This parameter can be measured by histochemical methods (Ki-67 antibody) or from the cytometric characteristics (percentage of S-phase-related tumor cells), and the boundary can be measured by the volume fraction of the internal vessels and the size of the external surface of the tumor. Since biochemical factors will contribute to the generation and establishment of these structural and thermodynamic features at the level of tissue organization, histochemical studies can uncover the correlation with these parameter alterations. Taking glycohistochemical determinants as an example for this hypothesis, the potential value of combining the results of immuno-/ligandohistochemistry with the data derived from the cytometric or syntactic structure analysis measurements and from the calculations based on thermodynamic theorems is illustrated.