Biomedical subjects
N Gale
Publications and source records attributed to N Gale.
Cervical metastases of head and neck squamous cell carcinoma correlate with loss of heterozygosity on chromosome 16q.
To assess the potential involvement of putative tumor suppressors or metastasis suppressors on chromosome 16q in head and neck squamous cell carcinoma (HNSCC), we have examined 42 primary HNSCCs for loss of heterozygosity (LOH) at 16q and correlated these findings with the occurrence of cervical nodal metastases and other clinical parameters. Seven of the 42 (17%) HNSCCs examined displayed LOH at chromosome 16q24. Three of the seven HNSCCs showed LOH at all of the informative loci analyzed along the chromosome arm, whereas the other four showed only loss of a subset of markers. When LOH at 16q was correlated with clinical parameters, there was no significant correlation with age, sex, clinical stage, T stage, N stage or survival. However, there was a correlation between LOH at chromosome 16q24 and involvement of cervical lymph nodes. Of the seven HNSCCs that had lost heterozygosity at 16q24, six had local metastases to lymph nodes indicating that LOH at 16q24 may have predictive value for the metastatic potential of HNSCCs.
Detection of human papillomaviruses in tissue specimens.
During the past decade, molecular methods based on the detection of viral DNA have become a key tool for the detection of human papillomaviruses (HPVs) in tissue. The methods can be divided into two groups: those in which tissue destruction is unavoidable for the detection of HPV DNA, and those in which the detection of viral DNA is performed in a way that allows tissue morphology preservation. Polymerase chain reaction is currently the most sensitive method for HPV detection and an excellent research tool. However, because of frequent contamination problems and lack of standardization, it is not readily applicable to diagnostic laboratories. The recent improvements in in situ hybridization have made it possible for this method to become the most appropriate method for routine detection of HPVs in tissue. At present, however, the use of at least two independent HPV DNA detection methods is indispensable for accurate determination of HPVs.
Quantitative pathology of laryngeal epithelial hyperplastic lesions.
We studied 40 laryngeal biopsies samples in order to ascertain the reliability of light microscopical criteria for subdividing laryngeal epithelial hyperplastic lesions (EHL) and carcinoma in situ as well as to determine the relationship between proliferative activity of their epithelial cells and the histological grade. The biopsies were divided into four groups in accordance with the Kambic-Lenart classification: simple, abnormal and atypical hyperplasia and carcinoma in situ. 10 cases in each group were included. The morphometrical analysis was carried out by a semiautomatic image analysis system. The proliferative activity was determined by the high percentage of cell nuclear antigen (PCNA) and Ki-67 positive epithelial cells and with counting nucleolar organizer regions (Ag-NORs) per nucleus. Our results suggest that measuring the nuclear area of the basal cells. augmented with basaloid cells and carcinomatous cells, is the most useful morphometrical method of differentiating three types of laryngeal EHL and carcinoma in situ, while the proliferative activity progressively increased with the degree of epithelial hyperplasia. Morphometrical methods and proliferative activity should be regarded as useful in conjunction with the traditional histopathological methods allowing more of objective grading of EHL.
Human papillomaviruses: a study of their prevalence in the epithelial hyperplastic lesions of the larynx.
This study investigated the prevalence of human papillomavirus (HPV) infection in various laryngeal epithelial hyperplastic lesions using the Kambic classification from simple hyperplasia to invasive squamous cell carcinoma. For detection of HPV infection polymerase chain reaction (PCR) with 3 different HPV consensus primer sets and in situ hybridization were used. The presence of the HPV DNA was detected in only 2 of the 88 specimens tested: HPV type 6 was detected in 1 case of simple hyperplasia and HPV type 16 in 1 case of invasive squamous cell carcinoma. In conclusion, our study suggests that most laryngeal epithelial hyperplastic lesions are not associated with HPV infection and that other pathogenic mechanisms are more important in the etiology of these lesions.
Langerhans and other immunocompetent cells in vocal cord epithelial hyperplastic lesions of patients with chronic laryngitis.
The aim of the study was to evaluate the intraepithelial and stromal density of Langerhans cells and lymphoid infiltrate in different stages of carcinogenesis in vocal cord biopsies of 24 randomly selected patients with chronic laryngitis. The Langerhans and lymphoid cells were counted using immunolabelling with antibodies against CD1a, S100, CD3, CD20, and CD68 on paraffin-embedded sections of 24 archival laryngeal vocal cord mucosa biopsy specimens, 6 classified as simple, 7 as abnormal, and 11 as atypical epithelial hyperplasia. Results were statistically evaluated using the Kruskal-Wallis and Wilcoxon sign rank tests. The mean number of Langerhans cells and T lymphocytes per mm2 of cross-sectioned epithelium was found to increase from simple to atypical hyperplasia. There were statistically significant differences in Langerhans cell density between atypical hyperplasia and each of the other 2 grades, simple and abnormal hyperplasia, with p < 0.05. Our study suggests the involvement of immune mechanisms, particularly cell mediated, during laryngeal carcinogenesis and the possibility that the assessment of Langerhans cell density might be of prognostic significance.
Langerhans cells in human papillomaviruses types 6/11 associated laryngeal papillomas.
Some studies have shown a reduced density of Langerhans cells (LCs) within epithelium infected by human papillomaviruses (HPV) types 16/18. However, data on a correlation between HPV types 6/11 infection and LCs have been missing. To solve this problem, we analysed 24 biopsy specimens of laryngeal papillomas, selected randomly, 20 multiple and 4 solitary. The presence of HPV 6 and 11 was proven by polymerase chain reaction (PCR) using 2 different sets of primers in 23 biopsy specimens. Abnormalities of the covering stratified squamous epithelium were graded according to the Kambic-Gale classification. LCs were immunohistochemically labelled with 2 different antibodies, CD1a and S100. Quantitative analysis was performed to determine the density of LC per mm2 in different grades of epithelial abnormalities covering laryngeal papillomas. Although no statistically significant differences in the mean number of LCs per mm2 of the cross-sectioned epithelium covering laryngeal papillomas were observed comparing simple, abnormal and atypical hyperplasia groups, the mean number of LCs per mm2 in laryngeal papillomas associated with HPV types 6/11 infection substantially exceeded that of the vocal cord surface epithelium in patients with chronic laryngitis.
Epidermal growth factor receptor, c-erbB-2 and p53 overexpressions in epithelial hyperplastic lesions of the larynx.
An immunohistochemical analysis of overexpression of epidermal growth factor receptor (EGFR), c-erbB-2, and p53 proteins was performed on 43 biopsies of laryngeal epithelial hyperplastic lesions (EHLL), classified according to the Kambic-Lenart classification, and in 11 cases of laryngeal carcinoma (SCCL). The aim of the present study was to determine whether there is a correlation between the staining patterns of these proteins and different grades of EHLL, and to reveal their possible prognostic value. We compared the staining patterns of atypical hyperplasia adjacent to cancer with the same type of lesions which have not turned malignant. p53 and EGFR overexpressions were detected in 28/54 (52%) and 33/54 cases (61%), respectively, and tend to increase with the degree of epithelial changes. The intensity of staining in various grades of EHLL adjacent to cancer was more pronounced than the same type of lesions which have not progressed to cancer. c-erbB-2 was weakly positive in the majority of cases, and changed from predominantly membranous in simple hyperplasia to cytoplasmic staining in abnormal and atypical hyperplasias. There was no significant statistic correlation between the amount of positive cells for all proteins and the grade of epithelial abnormalities. We conclude that the overexpression of each biomarker itself adds little predictive value over routine histomorphology, and cannot be regarded as a reliable prognostic factor for EHLL. However, the histologic characteristics of atypical hyperplasia together with the immunostaining patterns of EGFR and p53 up to two-thirds or more of the epithelial thickness could be considered a reliable pattern which correlates with the progression to cancer.
Correlation of histomorphological criteria used in different classifications of epithelial hyperplastic lesions of the larynx.
Different classifications of epithelial hyperplastic lesions of the larynx were proposed, but none of them has been generally accepted. The basic distinction among these gradings is evaluation of carcinoma in situ as a precancerosis or a distinct and separate entity. In the present study, atypical hyperplasia and carcinoma in situ are evaluated according to the proposed histomorphological criteria of the Kambic-Lenart classification. In an attempt to separate more objectively the histomorphological differences between these 2 lesions, in addition to traditional light microscopical examination, we also performed semiquantitative analysis with statistical evaluation using the Wilcoxon signed rank test. These results revealed a significant morphological and statistical difference comparing atypical hyperplasia and carcinoma in situ on the basis of the following criteria: abnormal mitotic figures (p = 0.005), mitotic activity (p = 0.014), nuclear pleomorphism (p = 0.006), cellular atypia (p = 0.005), dyskeratosis (p = 0.008), and stromal infiltration (p = 0.015). These results confirm our view that atypical hyperplasia and carcinoma in situ are 2 consecutive but different entities in the process of carcinonogenesis.
Human papillomavirus infection and expression of p53 and c-erbB-2 protein in laryngeal papillomas.
Laryngeal papilloma (LP) is the most frequent benign laryngeal epithelial tumor caused by human papillomaviruses (HPV) types 6 and 11. In the present study, we were interested in whether we can find any prognostic markers which might reflect the biological behavior of the covering epithelium in LP. We focused our attention on the determination of HPV infection, the detection of p53 protein, and c-erbB-2 protein in 24 biopsy specimens of LP. We confirmed the HPV 6 and 11 etiology in 23 of 24 LP. In these lesions the overexpression of p53 protein increased with the grade of epithelial abnormalities. The distribution of positive cells changed from scattered and focal, in simple and abnormal hyperplasia, to diffuse in atypical hyperplasia. It has been shown that in the presence of HPV types 6 and 11 found in LP, p53 can still preserve its tumor suppressor activity. Infection with HPV types 6 and 11 might therefore account for the significantly lower rate of malignant transformation in LP. Two staining patterns for c-erbB-2 protein were observed in the hyperplastic epithelium covering LP: membranous and cytoplasmic. With the increasing grade of epithelial abnormalities, cytoplasmic staining became predominant, and c-erbB-2 positivity sometimes occupied the whole epithelial thickness. This may represent either an alteration in the processing stability of the c-erbB-2 mRNA, gene amplification, or even an artefact.
The interpretation of leukoplakia in laryngeal pathology.
Leukoplakia is only a descriptive clinical term designating a white patch or plaque of the mucosa and must be complemented by histology. On the other hand, keratosis is an exclusively histological term denoting pathological production and accumulation of keratin on the surface of the laryngeal epithelium. Leukoplakia is usually keratosis, but not always. Keratosis can mask various epithelial changes, from simple hyperplasia to invasive squamous carcinoma and is only the superficially visible manifestation of an underlying pathological process. Keratosis means total replacement of superficial epithelial cells by keratin filaments, and dissolution of the nuclei. When nuclei are retained in keratinized cells, the process is termed parakeratosis. Therefore, keratosis can be classified as a separate entity only when histopathological examination reveals superficial keratotic changes accompanying a normal squamous epithelium. To identify the presence of keratosis in various benign laryngeal entities divided according to severity of epithelial abnormalities, and to determine whether keratosis has any prognostic value, we performed a retrospective analysis on bioptic material on 4,291 tissue specimens over a period of 15 years. Our results suggest that keratosis must be considered as only one sign of the disorder within the complex of other pathological changes and not as a distinct pathological entity. For this very reason, keratinization of the epithelial surface was not included among significant parameters used for the grading of epithelial changes into the particular group according to Kambic-Lenart classification.
Flow cytometric analysis of lymphocytes isolated from nasal polyps.
We analyzed by flow cytometry the expression of IL-2 receptors (alpha subunit-CD25) and ICAM-1 adhesion molecules (CD54) on T cells and subsets (CD4, CD8) isolated from nasal polyp tissue in allergic and non-allergic patients. We found a significant increase in IL-2 receptor and ICAM-1 molecule expression on T cells isolated from nasal polyp tissue compared to peripheral blood lymphocytes. We also found a significantly increased expression of ICAM-1 molecules on CD8+ cells in non-allergic compared to allergic patients. The latter may reflect a difference in cytotoxic immune response between allergic and non-allergic patients, but the result should be confirmed in a more extensive study including cytokine and immunoglobulin analysis. We hope that it would enable us to obtain a deeper insight into the local immune events and further to clarify the etiology and pathogenesis of nasal polyps and their relation to allergy.
Expression of Ki-67 antigen and proliferative cell nuclear antigen in benign and malignant epithelial lesions of the larynx.
In an attempt to analyse the proliferative activity in benign and malignant laryngeal epithelial lesions, and to determine the relationship to their histologic grade, we studied the expression of proliferative cell nuclear antigen (PCNA) and Ki-67 antigen on 20 squamous carcinomas, and on 30 biopsies of epithelial hyperplasia categorized according to the Kambic-Lenart classification into simple, abnormal, and atypical hyperplasias. In simple hyperplasia, both antibodies stained the nuclei of the occasional cells in the basal layer. In abnormal hyperplasia (mild dyplasia), positive cells occupied up to a third, and in atypical hyperplasia (moderate and severe dysplasia) they occupied from two-thirds to the entire epithelial thickness. In squamous carcinoma, we have found a statistically significant correlation between its grade and the percentage of Ki-67-(p < 0.01) and PCNA-(p < 0.00001) positive cells. Our results suggest that the proliferative fraction progressively increases with the degree of epithelial hyperplasia and the grade of carcinoma. We conclude that the patterns of immunoreactivity to PCNA and Ki-67 antigen correspond to the histologic grade of both benign and malignant epithelial lesions of the larynx. This method should be regarded as a useful adjunct to traditional histological techniques allowing more objective grading of benign and malignant epithelial lesions.
Unusual inflamed thyroglossal cyst.
The authors report a case of an unusual inflammatory reaction in a thyroglossal cyst. It consisted of broad papillary intraluminal projections covered by histiocytes and occasional multinucleate giant cells. This benign process should not be confused with a true papillary neoplasm, a rare complication of a thyroglossal cyst.
Laryngeal papillomatosis: molecular, histopathological, and clinical evaluation.
Molecular, histopathological, and clinical studies were carried out on a series of 79 laryngeal papillomas (LP) from 36 patients in order to investigate the hypothesis that juvenile and adult LP may represent a biological entity causally related to Human papilloma virus (HPV) infection. Using in situ hybridization with biotin-labelled probes and polymerase chain reaction, we detected human papilloma virus (HPV) 6/11 in 28 of 29 juvenile LP, in 26 of 30 adult multiple, and in 17 of 20 adult solitary LP. None of LP was found to harbour HPV types 16, 18, 31, 33, and 51. There were no clear-cut histological differences between juvenile and adult LP, the presence of koilocytosis was equally observed in both, and there was no prevalent type of epithelial hyperplasia in either form, except that all three cases of atypical hyperplasias (precancerous lesions) were found among adult patients. During a 14 year follow-up, no carcinomatous transformation of LP was observed. All juvenile LP in our study had frequent recurrences of the disease, however, numerous surgical procedures were also required in 16 of 27 adult patients. Our study supports Lindeberg's hypothesis of a similar pathogenesis for all forms of LP caused by the HPV types 6/11.
p53 immunoreactivity in oligodendrogliomas.
Data are presented on p53 protein presence in human oligodendrogliomas whose progress from low grade to anaplastic oligodendroglioma can be followed. Expression was evaluated by formalin-fixed paraffin-embedded section immunohistochemistry, using monoclonal PAb 1801 antibody. The frequency of p53 protein accumulation is related to the stage of tumor malignancy. All the samples (100%) of malignant oligodendrogliomas were positive for p53 protein. Of 14 type II oligodendroglioma samples, 9 were positive (64%) while among type I oligodendroglioma the positivity was 28%. The mean proportion of reactive cells was also higher in malignant oligodendrogliomas. However, mean intensity staining did not differ among various grades of tumors. Our results point to the direct link between p53 protein accumulation and the malignant stage of human oligodendrogliomas. However, the value of p53 protein accumulation in predicting malignant behavior of oligodendrogliomas requires further confirmation.
Catastrophic thrombus development despite systemic heparinization during coronary angioplasty: possible relationship to nonionic contrast.
Two cases of catastrophic thrombus formation during coronary angioplasty occurred shortly after the operators began using nonionic contrast. This occurred despite systemic heparinization, the adequacy of which was documented by activated clotting times (ACT). Both cases were resistant to balloon inflation and one was refractory to intracoronary thrombolysis. There is a considerable body of evidence documenting that low-osmolality contrast media, especially those that are nonionic, have less anticoagulant effect than standard contrast media. Several reports have also been published suggesting possible relationships between nonionic contrast and intravascular thrombus formation during coronary angiography and angioplasty. These data are reviewed and recommendations made for utilization of these contrast media.
Laryngeal hyperplastic lesions, follow-up study and application of lectins and anticytokeratins for their evaluation.
A retrospective study of 878 biopsy specimens from 692 patients with laryngeal hyperplastic aberrations was performed according to the Kambic-Lenart classification. Special attention was focused on 88 patients with persistent or recurring disease. In these carcinoma developed in 17 (2.4%) patients, 12 (1.7%) of whom had had atypical hyperplasia. We therefore propose that the term precancerosis, which so definitely implies cancer, should be replaced with the expression risky epithelium where nothing is determined in advance, but a careful follow-up of the patients is imperative. In particular cases of laryngeal hyperplastic lesions, mainly in abnormal and in atypical hyperplasias when the tissue specimens are cut tangentially, the exact identification and position of individual epithelial cells is essential. In such cases histochemical and immunohistochemical methods yield more precise evaluation. Lectins and cytokeratins provide good markers of epithelial maturation. These results contribute to a more useful evaluation of laryngeal hyperplastic lesions, crucial for the choice of adequate therapy.