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P Luzi

Publications and source records attributed to P Luzi.

At least 73 records · Page 4Linked to original sources
PubMed1992

Novel, contrast gradient-oriented, automated chromatin texture analysis. I. Feasibility study on nuclei from benign and malignant breast epithelial cell lines in fine needle aspirates.

Coarse granularity of nuclear chromatin texture is a prominent feature of most malignant cell lines. We have chosen the abrupt transition from eu- to heterochromatic foci (high contrast gradient [CG]) as a novel parameter for coarseness. This feature was quantified using automated image analysis of single nuclei in smears stained by the May-Grünwald-Giemsa technique. The principle of this approach consists of eliminating, with the help of subtraction between two image lowpass filters, the small grey level differences among pixels, so that only high CG values are retained on the digitized image. The sum of these distinctive microareas is then taken as a fraction of the area of the peripherally eroded nucleus, and this ratio is designated as contrast gradient index (CGI) per nucleus. This method was tested on fine needle aspirates from 11 patients with benign breast disease (BBD) and 14 with mammary carcinoma (CA). For each specimen, 60 nuclei were analyzed, with a measuring time per nucleus of about 1 min. A high significant distinction between epithelial cell populations in BBD and CA, respectively, was obtained by variance analysis of all CGIs per nucleus (p = 2 x 10(-18). The median and the mean values of CGI per specimen were the next best discriminators, followed by the modes and the standard deviation of CGI per specimen. The percentage of nuclei per specimen with CGI values of greater than 12 was also significantly greater in CA than in BBD.

Adolescent↗
PubMed1992

Quantitatively evaluated ultrastructural findings can add to the differential diagnosis between keratoacanthoma and well differentiated squamous cell carcinoma.

The differential diagnosis between keratoacanthoma (KA) and well differentiated squamous cell carcinoma (WDSCC) is not always easy to perform. Seven cases of KA and seven cases of WDSCC have been here analyzed by morphometry on ultrastructural sections and compared with normal epidermis. Parameters expressing the cohesivity among epithelial cells (numerical and surface density of desmosomes; volume density of intercellular space) were significantly different in KA and WDSCC, so that they may be useful in differential diagnosis. The Authors also questioned the nature of KA, suggesting a continuum between this lesion and WDSCC.

Carcinoma, Squamous Cell↗
PubMed1991

Morphometry and the differential diagnosis between peripheral neuroepithelioma and neuroblastoma.

The differential diagnosis based on morphology between neuroblastoma (NB) and peripheral neuroepithelioma (PN) is difficult, since these tumors share many architectural and cytological features. In this study, a morphometrical approach to this diagnosis is made by using nuclear (shape factors) and tissue (volume density of nuclei and stroma) parameters. Quantitative morphological analysis adds important information, which when used with clinical and biochemical data facilitates the distinction. In the majority of cases, nuclei of PN are significantly less round than those of NB and their profile is much more irregular. The density of neoplastic nuclei is significantly higher in PN. However, in a certain number of cases, even the morphometrical study confirms how difficult it may be to differentiate these two neoplastic entities, since the values of parameters are largely overlapping. This suggests the existence of a "continuum" of changing features between NB and PN, which may substantiate the hypothesis of a common histogenesis.

Adolescent↗
PubMed1990

Morphometric definition and grading of gastric intestinal metaplasia.

Type I and type III intestinal metaplasia in gastric mucosa have been examined using morphometric methods. Tissue (volume per cent gland, lumen, epithelium, goblet cell vacuoles) and nuclear parameters (area, with related standard deviation, and form factors) were used as indicators of gland crowding, nuclear-cytoplasmic ratio, nuclear atypia, and pleomorphism. In type III intestinal metaplasia, there is significantly (i) greater nuclear pleomorphism, (ii) a higher nuclear-cytoplasmic ratio, and (iii) smaller and less numerous goblet cell vacuoles in both the upper and the lower parts of the crypts. These two parameters have significantly higher values in the lower than in the upper part of individual crypts. No cell population with large pleomorphic nuclei characterized type III metaplasia, though there was more variation in nuclear size.

Adult↗
PubMed1989

Ultrastructural study of pseudo-Kaposi's sarcoma (Bluefarb-Stewart type).

An ultrastructural study of the skin lesion of a young patient affected by pseudo-Kaposi's sarcoma of the Bluefarb-Stewart type (BSS) is reported. The neoplasm consisted of a proliferation of vascular structures mostly consisting of a solid bud of endothelial cells surrounded by a thinned and polystratified basement membrane and several pericytes. Both endothelial cells and pericytes were of normal ultrastructural appearance. Intervascular "stromal" cells were few and morphologically identified as macrophages and/or phagocytic fibroblasts. Masses of hemosiderin were detected outside the cells and in the macrophages, endothelial cells, and pericytes. Intracytoplasmatic crystalloid inclusions similar to those found in fetal endothelium and hemangiomas were observed in a few endothelial cells. These findings are different from those of previously reported cases of pseudo-Kaposi's sarcoma and may be helpful in distinguishing Kaposi's sarcoma from BSS. The role of immunodeficiency in the onset of BSS is discussed.

Adult↗
PubMed1989

Morphometric distinction of low- and high-grade dysplasias in gastric biopsies.

Substantial agreement has previously been demonstrated between qualitative and morphometric grading of gastric dysplasia. In the present study, a further attempt is made to quantitatively define the dysplastic changes in relation to associated benign or malignant changes of gastric mucosa. In total, 232 cases were studied and were associated with benign peptic ulcer (89 cases), histologically proven gastric cancer (88 cases), and gastritis-associated mild, moderate, and severe dysplasias (55 cases). The analysis showed that one discriminant function consisting of seven morphometric features is sufficient to separate the regenerative and cancer-associated cases. The classification results obtained on the basis of this discriminant function in both training and testing sets are encouragingly similar, indicating that the classification is reliable. This was further confirmed by the results of the application of this rule in the mild, moderate, and severe dysplasia biopsies (the above-mentioned gastritis-associated cases) used in a previous study. The quantitative analysis permits two grades, instead of three, to be distinguished: low-grade and high-grade dysplasia.

Biopsy↗
PubMed1989

The nuclei in cutaneous malignant melanoma, stage I, are smaller in survivors than in non-survivors.

Cutaneous melanoma, stage I, from 35 survivors at 5 year follow-up and 16 non-survivors were studied. Mean nuclear area in the superficial layer was significantly larger than in the deep layer both in survivors and non-survivors, but the ratio between nuclear area in superficial and deep layers (so-called maturation index) did not differ between survivors and non-survivors. In comparison with the survivors, the mean nuclear area of non-survivors was significantly larger both in the superficial (51.1 microns2 vs 43.7 microns2, p less than 0.01) and deep (42.9 microns2 vs 36.4 microns2, p less than 0.05) layer. This points to a general increase in nuclear areas in metastasizing tumors. Furthermore, the coefficient of variation of nuclear area [(standard deviation/mean) x 100] was not different between survivors and non-survivors, either in the superficial or in the deep layer. Inspection of histograms of areas of 1000-2000 nuclei per case in 20 random cases (10 survivors and 10 non-survivors) showed a homogeneous increase in nuclear area in non-survivors. None of the histograms revealed a cell clone with especially large nuclei. These data show that the increased mean nuclear area in non-survivors is due to a homogeneous increase of all nuclei throughout the tumor and not to a special cell clone with large nuclei within nuclei of otherwise normal size. The difference in mean nuclear area in superficial and deep layers indicates that careful selection of nuclei in either of these layers is essential to obtain reproducible and comparable results with interactive morphometry.

Cell Nucleus↗
PubMed1988

Primary carcinoid tumor of kidney. Light and electron microscopy, and immunohistochemical study.

We present a case of primary renal carcinoid tumor with the appearance of type B carcinoid with trabecular and ribbon-like structure. All the immunohistochemical stains were negative. Electron microscopy revealed numerous cytoplasmic granules with polar distribution and masses of intermediate microfilaments. We believe only 8 cases have been reported in the literature.

Actin Cytoskeleton↗
PubMed1988

Mantle zone lymphoma: a morphometric comparison with centrocytic and immunocytic lymphomas and reactive secondary follicles.

Nuclear size and shape of lymphoid cells were evaluated morphometrically in the mantle zone lymphoma, immunocytic lymphoma, and centrocytic lymphoma, and were compared with those of reactive secondary follicles. Shape factors (forms Ar, Ell, Pe, and Dia) have been used to quantitatively define the most frequent nuclear profiles. One of the testing sets consisted of the nuclei of the light, dark, and mantle regions of reactive nodes, as well as those of the centrocytic lymphoma, immunocytic lymphoma, and the mantle-fashion growth lymphoma. Another testing set was made up of only the three types of lymphoma and was used for evaluating the variability of shapes within these groups by means of a pattern recognition algorithm. The content of reactive T lymphocytes was assessed in all cases by immunohistochemistry. The results of transforming centroid values into geometric shapes by computer modelling indicated that only minor geometric differences existed between the a priori qualitatively chosen nuclear types and those modeled a posteriori by computer. All the nuclear types were found in each of the reactive regions and in each of the lymphomas. However, highly significant differences of distribution were detected among the three categories of lymphoma and between each reactive region and each lymphoma. The cases of centrocytic lymphoma showed constant findings in terms of nuclear composition, while lymphomas with mantle-fashion growth and the examples of immunocytic lymphoma showed significant variability. These observations confirm that the centrocytic lymphoma represents a distinct entity, although its normal counterpart is still unknown, and question the view that the immunocytoma and the mantle zone lymphoma correspond to homogenous categories of non-Hodgkin's lymphomas. In addition, since all the qualitatively and quantitatively detected nuclear types were found in all the reactive regions and in all the lymphomas, albeit with different distributions, it has to be assumed that only numerical differences exist among the various lymphomas and the reactive regions.

Adult↗
PubMed1988

Morphometric assessment of the biological potential of human papillomavirus infections in the uterine cervix.

A series of 69 punch biopsies derived from 513 women prospectively followed up for cervical human papillomavirus (HPV) infections (including HPV lesions with and without cervical intraepithelial neoplasia; HPV-CIN, HPV-NCIN), and 42 control cases (consisting of normal epithelia, and classical CIN lesions) were analyzed morphometrically, using a semiautomatic image analyzer (IBS I-KONTRON), to assess the value of morphometric measurements in discriminating between HPV lesions and CIN, and to find out whether these methods are useful in predicting the outcome of cervical HPV infections. Nuclear area and the form factors Ell, Ar, and Pe were calculated on fifty nuclei in each of the three layers of epithelium; deep, intermediate and superficial. The reproducibility of the measurements was calculated for intra- and interobserver variation. HPV typing was completed using the in situ hybridization technique with DNA probes for HPV 6, 11, 16, 18 and 31. No significant differences were detected by using the form factors (Ell, Ar, Pe), when HPV lesions were compared with the normal epithelium, or with classical CIN lesions, in any of the epithelial layers. The nuclear area was significantly larger in all the epithelial layers in HPV-CIN I, and HPV-CIN II lesions as compared with CIN I and CIN II cases (p less than 0.001), p less than 0.001, p less than 0.005 and p less than 0.001, for deep, intermediate and superficial layers between HPV-CIN I/CIN I, and for all layers in HPV-CIN II/CIN II comparisons, respectively). This was also true when the values of nuclear area in HPV-NCIN I, HPV-CIN II and HPV-CIN III lesions were compared with the normal epithelium (p less than 0.001 for all layers). In the most severe lesions, no significant differences existed between HPV-CIN III and CIN III cases. Nuclear area measurement could not predict, however, the HPV type found in the lesion, or their natural history established by prospective follow-up.

Cervix Uteri↗
PubMed1988

Primary endobronchial actinomycosis.

A male farmer referred for fever, cough and haemoptysis, presented, at bronchoscopic examination, a large mass occluding the middle lobe bronchus. No lung involvement was visible on chest X-ray. Histological examination showed an actinomycotic granule in the bronchial submucosa. The histological findings indicate that aspiration of contaminated material from the upper alimentary tract may have caused the disease.

Actinomycosis↗
PubMed1988

Comparative morphometric analysis of nuclear area and shape in peripheral T-zone lymphomas and in paracortical areas of normal and reactive lymph nodes.

The areas and shapes of cell nuclei were morphometrically analyzed in peripheral T-zone lymphomas, which have a characteristic nuclear pleomorphism, as well as in paracortical areas of normal and reactive lymph nodes; the aim of the study was to compare the neoplastic and nonneoplastic lymphoid cell populations. Although the means and standard deviations (SDs) of nuclear area and shape features differed significantly between the T-zone lymphomas, reactive nodes and normal nodes, there was considerable overlap between the lymphomas and the reactive lymph nodes in all of the features investigated. Therefore, the composition of populations of nuclei was studied. In lymphomas, the frequencies of regular and irregular nuclei were about the same in all nuclear area classes, whereas increasingly larger nuclei had an increasingly regular shape in reactive lymph nodes. An attempt to classify the cells, divided into those with small nuclei (less than 25 sq microns) and those with large nuclei (greater than 25 sq microns), on the basis of their morphometric shape features showed the usefulness of form factors in the class of nuclei with a large area. The results show that, while means and SDs of nuclear area and shape are not very accurate descriptors of the differences between the T-zone lymphomas and nonneoplastic lymph nodes, analysis of the percentage of regularly shaped nuclei in a certain nuclear area class can describe the differences much more accurately. The compositional differences in nuclear shape are in agreement with subjective impressions and can objectively support the pathologist's qualitative impression of pleomorphism in malignant T-zone lymphomas.

Adult↗
PubMed1987

Gastric dysplasia: a stereological and morphometrical assessment.

The grading systems of gastric dysplasia suffer from the lack of criteria that separate the changes with an acceptable reproducibility. Repeatable and objective grading of the lesion can be obtained by morphometrically measuring histological criteria normally employed in qualitative grading. In 54 consecutive antrum biopsy specimens in which a blind, independent agreement on the grade of dysplasia had been reached between four independent pathologists, stereological and nuclear morphometrical features have been studied. Single variate, bivariate and multivariate analyses have been performed. Architectural parameters, such as volume and surface densities of glands and epithelium, are especially good discriminators both between mild and moderate, and between moderate and severe dysplasia. Features describing arrangement and shape of nuclei, and nucleolar size are of additional help in improving the objective distinction between moderate and severe dysplasia.

Adult↗
PubMed1987

Endocrine inactive pituitary carcinoma metastasizing to cervical lymph nodes: a case report.

A 64-year-old woman experienced an episode of disorientation in relation to time, place, and people, as well as of visual defect and impaired balance. Physical examination showed a bitemporal hemianopsia and truncal ataxia. Computerized tomography of the skull revealed a sellar mass consistent with the diagnosis of pituitary adenoma. The patient progressively lost consciousness and died. At postmortem examination, a pituitary neoplasm with arachnoid metastases was present. Metastatic cervical lymph nodes were also detected. Histologic aspects of the primary tumor and of lymph node metastases were quite similar. Immunohistochemical investigation revealed the epithelial origin of the neoplasm and failed to disclose endocrine activity. At ultrastructural examination, the cells of the primary tumor and of the metastases lacked specific granules. These findings support the evidence of a primary metastasizing pituitary carcinoma.

Carcinoma↗
PubMed1987

Morphometry for the prognosis of acute lymphoblastic leukemia in childhood.

The morphology of acute lymphoblastic leukemia is of prognostic significance, but due to the qualitative subjective nature of the assessment, disagreement between pathologists may be considerable. In order to investigate the adjuvant potential of morphometry, the present study was undertaken. Morphometry was applied in 21 children between 2 and 10 years of age with acute lymphoblastic leukemia (ALL) with a follow-up of at least 5 years. Of these, 9 patients died, 12 (57.1%) survived for at least five years (maximally 12 years). Morphometry appeared to have an important prognostic value, independent of the FAB classification currently in use. Combination of the nuclear-cell area ratio and the cell area gave a rather good discrimination, although these quantitative data from a morphological continuum. The positive results of this pilot study point to the necessity of evaluating the data on a larger material.

Cell Nucleus↗
PubMed1987

Correlation between immunohistochemically determined oestrogen receptor content, using monoclonal antibodies, and qualitative and quantitative tissue features in ductal breast cancer.

Previous studies have shown that oestrogen receptor content in breast cancer was correlated with qualitative and also, more strongly, with quantitative nuclear features in tissue sections. However, even with the better reproducible quantitative microscopical assessments, the variance in the correlation with oestrogen receptor was considerable. This might be due to the implicit problems of oestrogen receptor determination with the biochemical assay. Therefore, receptor content was studied using monoclonal antibodies in 50 consecutive invasive ductal breast cancers. Oestrogen receptor status was compared with qualitative features and with the mean and standard deviation of the nuclear area, morphometrically evaluated on immunostained and adjacent haematoxylin and eosin stained sections. In agreement with earlier observations, nearly all tumours with prominent elastosis were oestrogen receptor positive; but a minority of negative cases also showed elastosis. The correlation between the other qualitative features and receptor status was weak. A significant inverse correlation (P less than 0.001) existed between the receptor status and the mean and standard deviation of the nuclear area. Even with the highly reproducible morphometrical analysis, correlation between nuclear oestrogen receptor content and quantitative nuclear features was relatively weak. This might indicate that receptor status and nuclear morphometric features reflect different biological characteristics of breast cancers.

Adult↗