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C L Alons

Publications and source records attributed to C L Alons.

16 recordsLinked to original sources
PubMed1986

Distribution of T-lymphocyte subsets in different portions of sarcoid granulomas: immunohistologic analysis with monoclonal antibodies.

The numbers and the distribution of T-lymphocyte subpopulations in lymph node granulomas from 11 patients with sarcoidosis were studied in cryostat sections by an immunoperoxidase technique. Greater numbers of helper T lymphocytes (Leu-3+) were found at the periphery than in the central portion of the same granuloma. Most of the suppressor T lymphocytes (OKT8+) were present at the periphery of the granulomas. In addition, the Leu-3a/OKT8 ratio varied from 0.7 to 1.8 in the outer compartment, while in the central portion of the granuloma much higher values (3 to 20) were found. These different distribution patterns of T-lymphocyte subsets provide evidence for two different compartments with different immune reactions in sarcoid granulomas.

Adult↗
PubMed1985

Quantitative morphology. A study of the trophoblast.

It is difficult to predict the possible development of a malignant trophoblastic tumor after the evacuation of a hydatidiform mole. In order to help resolve this difficulty, a morphometric study has been carried out. The mean nuclear area of the trophoblast in a group of hydatidiform moles, followed by a trophoblastic malignancy, was found to be statistically significantly larger than that of the trophoblast in a group of hydatidiform moles which were not followed by malignant trophoblastic disease. However, the mean trophoblast/nontrophoblast ratio in villi demonstrated no statistically significant difference between those 2 groups of hydatidiform moles. Therefore it is not advisable to grade hydatidiform moles on the basis of trophoblastic proliferation alone. It is suggested that the trophoblastic lining of hydropic villi in the placental tissue of hydatidiform moles has malignant features already, but these are more pronounced in those hydatidiform moles which are subsequently followed by a choriocarcinoma.

Choriocarcinoma↗
PubMed1985

Digitized image processing and pattern recognition in dental radiographs with emphasis on the interdental bone.

Diagnosis of bone lesions on dental radiographs can be difficult due to the irregular trabecular pattern and subjectivity on the part of the observer. The purpose of this study is to improve the recognition of bone lesions by means of objective computer-aided pattern recognition techniques. This article describes a method for the separation of teeth and bone regions in the image to facilitate further analysis, especially of the interdental bone.

Alveolar Process↗
PubMed1985

Digitized pattern recognition in the diagnosis of periodontal bone defects.

Radiography is an important tool in the diagnosis of periodontal bone lesions. Due to subjective factors in the interpretation by the observer, however, an error-free diagnosis of bone lesions in an early stage is very difficult. The aim of this study was to reduce the influence of observer subjectivity by means of computer-assisted image processing and pattern recognition in dental radiographs. The findings of the study show that periodontal lesions can be recognized and described in an objective way by means of digitized pattern recognition.

Alveolar Process↗
PubMed1985

Quantitative morphometry of squamous cell hyperplasia of the larynx.

The histopathological diagnosis of squamous cell hyperplasia of the larynx is very subjective. Since morphometry is highly reproducible, this method was applied to routine processed slides of 45 such lesions to assess objectively the epithelial characteristics. In each case measurements of nuclei of 50 cells in the basal, intermediate, and superficial cell layers were carried out. The data were analysed statistically. The findings suggest that quantitative morphometry may be helpful for the histopathological classification of squamous cell hyperplasia of the laryngeal mucosa.

Cell Nucleus↗
PubMed1983

A quantitative histomorphologic analysis of lymph node granulomas in Sarcoidosis in relation to radiological stage I and II.

In a detailed study of granulomas in lymph nodes of 19 patients with Sarcoidosis we assessed and correlated a number of features, with size, development and radiographic staging of the disease. Except with the epithelioid cells the number of constituent cells (lymphocytes, giant cells and polymorphs), size, confluency and degree of necrosis of the granulomas were found to be very variable within a single gland. This indicates that the granulomas are in different stages of activity at a given time. All the features studied showed little or no correlation with the radiographic staging, which suggests that the latter is not a good index of the extent of the disease.

Adult↗
PubMed1983

Analysis of the performance of pathologists in the grading of bladder tumors.

Fifty-seven transurethrally resected bladder tumors were analyzed to determine whether different pathologists, using the World Health Organization grading system, graded the same bladder tumor differently (interindividual consistency) and whether the same pathologist graded a bladder tumor differently at different times (intraindividual consistency). Disturbingly high inter- and intraindividual inconsistency in the grading of bladder tumors was found. All pathologists showed essentially the same degree of intraindividual inconsistency: In almost 50 per cent of cases the tumor was graded differently at different times by the same pathologist. The inconsistencies might invalidate the usefulness of bladder tumor grading in clinical decision-making.

Humans↗
PubMed1983

Morphometric grading of bladder tumors in comparison with histologic grading by pathologists.

The authors describe the results of the grading of bladder tumors using morphometry and then compare these with results of histologic grading of the same tumors by different pathologists. Nuclear sizes of cells obtained from superficial and deep cell layers of each carcinoma and from giant cells were measured in 27 cases in which histologic tumor grading by different pathologists was unequivocal. In cells from all three areas, nuclear area increased with higher tumor grade. However, tumors of grades I and II showed significant differences in the size only of the large cells. It is concluded that morphometry is a valuable tool in the objective grading of bladder tumors, with the exception of carcinoma in situ lining the bladder lumen.

Carcinoma↗
PubMed1981

The prognostic significance of morphometry in T1 bladder tumours.

Only 3% of patients with T1 bladder tumours die of bladder carcinoma within 5 years (Williams, Hammonds & Saunders 1977), therefore these patients are initially treated conservatively. There would however be benefits from being able to predict which patients should be treated more aggressively. Morphometry was applied to quantitate characteristic microscopical features of the removed T1 tumours in 16 patients who had survived for five years and in seven patients dead from the tumour, in order to evaluate the prognostic value of this method. The measurements of nuclear and cytoplasmic areas were made on routine H & E sections with a graphic tablet (ASM, Leitz). Statistical analysis of the obtained data revealed that there were significant differences between the two groups. It indicated that morphometric parameters of T1 bladder tumours can have prognostic as well as therapeutic significance which will be further tested in a prospective study.

Aged↗
PubMed1981

Learning from quantitation.

An important question in the effective use of quantitation in cytology is how to make the link between mathematical parameters and the cytologist. As an example, an investigation is discussed in which cell images from benign mesothelial proliferations were distinguished by quantitative characteristics from those of malignant mesotheliomas originating in the pleura and peritoneum. The significant differences between the three groups in nuclear size, cytoplasmic size and nuclear-cytoplasmic (N/C) ratio could partly be explained by the vacuolation patterns of the exfoliated mesothelial cells in each. Moreover, the primary site of the tumor could be predicted by the quantitative cell parameters. The characteristics of cytologic images, once known to be important, are easily incorporated into standard diagnosis. Thus it now seems possible for the cytologist to differentiate between the three groups by using the cytomorphologic features that relate to the computed parameters. This shows the value of translating computerized parameters into cytomorphologic criteria.

Ascitic Fluid↗
PubMedDate not supplied

The prognostic significance of morphometry for squamous cell hyperplasia of the laryngeal epithelium.

Laryngeal biopsies of squamous cell hyperplasia with atypia were graded by means of morphometry, using five non-correlated nuclear parameters preselected with linear discriminant analysis, and were tested for their prognostic significance, in a follow-up study. Fifty-two biopsy specimens were obtained from 18 patients who were merely followed and if necessary underwent a repeated biopsy examination. The lesions of 10 patients progressed to invasive carcinoma. In 8 patients the second or further biopsies were again classified as squamous cell hyperplasia with atypia. For both groups the mean follow-up period was 7.2 years (range: 3 1/2-11). In the progressive group 73% of the biopsies were morphometrically classified as prognostically unfavourable, whereas the clinical outcome on the basis of the last biopsy was correctly predicted for 6 out of the 10 cases (mean probability: 94%), the other 4 cases were 'mis-classified', although for 3 cases with a low probability (mean: 60%). For a valuable morphometrical classification of lesions of individual patients, the results as presented are still insufficient. Morphometrical classification probabilities may be improved when the numbers of untreated patients with squamous cell hyperplasia with atypia do increase.

Adult↗
PubMedDate not supplied

The clinical relevance of classification of squamous cell hyperplasia of the larynx by morphometry.

By means of morphometry, differentiation between the classes of laryngeal squamous cell hyperplasia can easily be performed, mutually (Kleinsasser's classification) and in comparison with normal epithelium. It is rather difficult, however, to distinguish between class II (hyperplasia and atypia) and class III (carcinoma in situ). In the group of class II lesions, two groups of patients could be differentiated: a prognostically favourable and an unfavourable group. When using a linear discriminant analysis, the two groups mentioned could be distinguished morphometrically. In histopathological examination, lesions classified as hyperplasia and atypia (class II), must also be examined with morphometry, because in this way the group at risk can be traced.

Biopsy↗
PubMedDate not supplied

Discrimination between primary pleural and primary peritoneal mesotheliomas by morphometry and analysis of the vacuolization pattern of the exfoliated mesothelial cells.

Cells exfoliated from primary pleural mesotheliomas differ significantly from those from primary peritoneal tumors. In a quantitative study, it was shown that the pleural cells have larger nuclei, a more pronounced anisokaryosis and a higher nuclear-cytoplasmic ratio and, therefore, appear more malignant than the peritoneal cells, which have abundant cytoplasma and small nuclei. The differences in quantitative parameters were due to a more extensive vacuolization and consequent cytoplasmic distension, combined with nuclear compression in the case of peritoneal mesotheliomas. The morphometric parameters and the vacuolization patterns of cell populations in cases with both pleural and peritoneal involvement correlated with the data of the primary tumor regardless of the fluid in which the cells were found. This finding indicates the transcoelomic metastatic properties of malignant mesothelioma.

Ascitic Fluid↗