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J Weyler

Publications and source records attributed to J Weyler.

At least 37 records · Page 2Linked to original sources
PubMed1999

Angiogenic cytokines in mesothelioma: a study of VEGF, FGF-1 and -2, and TGF beta expression.

Vascular endothelial growth factor (VEGF), acidic and basic fibroblast growth factors (FGF-1 and -2), and transforming growth factor beta (TGFbeta) are potent angiogenic cytokines. Malignant mesothelioma of the pleura presents with a high intra-tumoural microvascular density (IMD) which also has prognostic relevance. This study was designed to verify the immunohistochemical expression of the angiogenic cytokines in mesothelioma as well as in non-neoplastic human mesothelial cells and to study the individual as well as the combined expression of these cytokines in mesothelioma in relation to both IMD and prognosis. In addition, four mesothelioma cell lines were studied by ELISA for the secretion of VEGF and FGF-2 in their supernatants and were shown to contain high levels of both of these cytokines. Immunohistochemically, VEGF, FGF-1 and -2, and TGFbeta immunoreactivity was present in 81, 67, 92 and 96 per cent of mesotheliomas, and in 20, 50, 40, and 10 per cent of samples of the non-neoplastic mesothelium, respectively. Co-ordinate expression of the cytokines was observed whereby mesotheliomas expressed more than one cytokine. The combined immunohistochemical expression levels for all four cytokines correlated significantly with both IMD (p=0.01) and prognosis (p=0. 0013). When studied individually, high FGF-2 expression correlated best with more tumour aggressiveness and worse prognosis for mesothelioma (p=0.0011). There was no significant correlation between prognosis and immunoexpression of VEGF (p=0.07), FGF-1 (p=0.3), or TGFbeta (p=0.1), or between IMD and any of the cytokines studied individually. These data support the assertion that selective angiogenic cytokines might contribute to the progressive changes of mesothelioma by tumour angiogenesis.

Biomarkers, Tumor↗
PubMed1999

Angiogenesis in cervical intraepithelial neoplasia and the risk of recurrence.

OBJECTIVE: We sought to investigate whether angiogenesis can predict the risk of recurrence of cervical intraepithelial neoplasia after treatment. STUDY DESIGN: Microvessel density was studied in 75 patients with grade 3 cervical intraepithelial neoplasia and in 20 patients with microinvasive squamous carcinoma (International Federation of Gynecology and Obstetrics stage IA1) of the uterine cervix by staining representative tissue sections with the specific endothelial marker anti-CD31. The microvessel density was determined with a digital image analyzer. The results were correlated with clinical and histopathologic data. RESULTS: The mean vessel density was 264 per field (range, 86-674 per field) in grade 3 cervical intraepithelial neoplasia and 378 per field (range, 161-848 per field; P = .001) in microinvasive squamous carcinoma. Thirteen patients with grade 3 cervical intraepithelial neoplasia had recurrent cervical intraepithelial neoplasia (microvessel density, recurrent vs nonrecurrent; not significant). Multiple regression analysis in the noninvasive group confirmed that the mean vessel density (P = .121) had no prognostic value. Furthermore, it showed that the age at diagnosis (P = .011), menopausal status (P = .052), and treatment modality (P = .022) proved to be independent prognostic factors for recurrence. CONCLUSIONS: During the progression from noninvasive to microinvasive cervical carcinoma, the microvessel density increases significantly. However, the vessel density does not predict recurrence of noninvasive lesions.

Adult↗
PubMed1999

Prospective study of intratumoral microvessel density, p53 expression and survival in colorectal cancer.

Adjuvant treatment of patients with colorectal cancer is hampered by a lack of reliable prognostic factors in addition to the clinicopathological staging system. A poorly defined but considerable fraction of Astler-Coller stage B patients will experience tumour recurrence, and some of the stage C patients will probably survive for a prolonged time after surgery without adjuvant treatment. Assessing parameters related to tumour angiogenesis has provided valuable prognostic information in different tumour types. The formation of new microvessels is part of the malignant phenotype in the majority of tumours. Alterations in tumour-suppressor genes, such as the p53 gene, or oncogenes, such as the ras gene, have been found to be responsible for changing the local balance of pro- and antiangiogenic factors in favour of the former. In this prospective study, intratumoral microvessel density (IMD) was assessed by immunostaining tissue sections for CD31 and counting individual microvessels in selected and highly vascular regions in specimens of 145 colorectal cancer patients. p53 protein overexpression was semiquantitatively determined after immunohistochemistry. In both uni- and multivariate analysis, high IMD was significantly associated with shorter survival in the patients undergoing surgery with curative intent (Astler-Coller stages A-C). p53 added prognostic power to IMD, both in Astler-Coller stage B and stage C patients. An association between IMD and mode of metastasis was also noted. High IMD was strongly associated with the incidence of haematogenous metastasis during follow-up, but not with the presence of lymphogenic metastasis observed at surgery. This study confirms the results of previous retrospective analyses of IMD and survival in colorectal cancer and warrants a clinical validation by randomizing stage B tumour patients with high IMD and p53 overexpression between adjuvant treatment or not.

Adult↗
PubMed1999

Can Flemish women in semi-rural areas be motivated to attend organized breast cancer screening?

BACKGROUND: The implementation of organized breast cancer screening in Flanders was prepared by means of pilot projects within a multicenter study. In the semi-rural district of Kontich (Province of Antwerp, Flanders) a pilot project was performed using a mobile screening unit. Compared to international standards, the attendance rate for this pilot project (i.e. 34%) was low. Non-organized screening, which already exists in Flanders, at least partly explains this low attendance rate for the organized screening. The main purpose of our study was to investigate the experience of the pilot target group with respect to the organized breast cancer screening in the district of Kontich, in order to maximize the conditions for a high attendance rate in the organized breast cancer screening programme throughout Flanders. METHODS: With a random numbers procedure, performed by the computer, 500 women were selected among those who were invited to the first screening round of the breast cancer screening programme in the district of Kontich (n = 6,897). These 500 randomly selected women were asked to cooperate with a face-to-face interview. The questionnaire used dealt with the different aspects of the organized mammographic screening which were expected to influence the decision to attend. RESULTS: There were 348 women who responded to the questionnaire (69.6%): 138 of them were attenders and 210 were non-attenders at the organized breast cancer screening. Attenders and non-attenders at the organized breast cancer screening in the district of Kontich had different views about various aspects of the screening programme. The percentages of those who thought that an item was important or very important to them, were for the 138 attenders and the 210 non-attenders respectively: "to receive a personal invitation letter": 90.6 vs. 48.1% (p < 0.05); "a preliminary visit to the GP": 9.4 vs. 34.3% (p < 0.05); "possibility of examination outside business hours": 15.9 vs. 30.0% (p < 0.05). CONCLUSIONS: Although the putting into action of a mobile unit in the semi-rural area of the district of Kontich was productive, the attendance rate was still too low compared to international standards. To increase the attendance rate, the following interventions should be considered: devising the personal invitation letter in a more attractive way, activating and stimulating the important motivational role of the GP in persuading women to attend the organized screening programme and offering the invited population the possibility to have a mammographic examination performed outside business hours. Appropriate measures are being explored.

Aged↗
PubMed1999

Silicone oil tamponade in the vitreoretinal surgery.

This retrospective study aimed to evaluate the influence of a temporary silicone oil (SiO) tamponade on intraocular pressure (IOP). We reviewed 131 procedures with a temporary SiO tamponade for different indications. Visual outcome and anatomic results after the SiO removal were also analyzed. Relatively good visual and anatomic results can be achieved by a temporary SiO tamponade with an acceptable complication rate.

Adolescent↗
PubMed1998

Syndecan-1 expression in malignant mesothelioma: correlation with cell differentiation, WT1 expression, and clinical outcome.

Syndecan-1 binds basic fibroblast growth factor (bFGF), modulates neovascularization, plays a role in epithelial differentiation and is up-regulated by WT1. Malignant mesothelioma of the pleura is one of the most aggressive tumours known and expresses high levels of angiogenic growth factors. This study has analysed syndecan-1 expression in mesothelioma tumours and cell lines by immunohistochemistry and immunoblotting, using anti-syndecan-1 antibody directed against the core protein, and has examined its relation to morphology, bFGF, WT1, and intra-tumoural microvascular density (IMD). Shedding of syndecan-1 in the conditioned medium of mesothelioma cell lines was detected in variable amounts. These studies indicate that (1) there is no correlation of syndecan-1 with either bFGF expression or IMD in mesotheliomas in vivo; (2) syndecan-1 is strongly expressed in the epithelial type of mesothelioma and in the epithelial component of biphasic mesotheliomas and the expression is reduced or lost in sarcomatoid differentiation; together with the finding that (3) syndecan-1 correlates with WT1 immuno-expression, this suggests that syndecan-1 might relate to the differentiation state of mesothelial/mesothelioma cells; and (4) syndecan-1-positive tumours are associated with a longer survival (p = 0.02) than mesotheliomas with no or little syndecan-1 expression, on univariate analysis. These findings therefore indicate that syndecan-1 can be an important prognostic indicator in mesotheliomas and its loss may be important in the epithelial-mesenchymal transformation of mesothelioma cells.

Adenocarcinoma↗
PubMed1998

Expression of bcl-2 in invasive and in situ carcinoma of the uterine cervix.

OBJECTIVE: The oncoprotein bcl-2 inhibits apoptosis. The purpose of this study was to assess the expression of bcl-2 in human cervical carcinoma and to correlate this with clinicopathologic parameters. STUDY DESIGN: Immunohistochemical staining for bcl-2 protein (MoAB clone 124) was performed on operative tissue specimens from 22 patients with carcinoma in situ of the cervix and from 137 patients with invasive cervical carcinoma (International Federation of Gynecology and Obstetrics stages I to IV). The immunoreactivity of bcl-2 was scored as positive (> or = 5% staining cells) or negative (< 5% staining cells). RESULTS: Eighty-two percent of in situ carcinomas and 61% of invasive cervical carcinomas were bcl-2 positive. Expression of bcl-2 was correlated to tumor stage (p < 0.001) and to presence of vascular (p < 0.005) or lymphatic tumor (p < 0.023) permeation. In univariate analysis there was a strong relationship between bcl-2 expression and overall survival (p < 0.001). In multivariate analysis bcl-2 expression (p < 0.001), International Federation of Gynecology and Obstetrics stage (p = 0.011), and presence of lymphatic permeation (p = 0.014) proved to be independent prognostic factors. CONCLUSIONS: Expression of bcl-2 is lost during tumor progression and is a strong prognostic parameter, suggesting that the regulation of apoptosis plays an important role in the behavior of cervical carcinomas. Better understanding of the mechanisms involved may lead to improved medical treatment strategies.

Adult↗
PubMed1998

Quantification and prognostic relevance of angiogenic parameters in invasive cervical cancer.

Tumour stromal neovascularization was investigated in 114 invasive and 20 in situ carcinomas of the uterine cervix by staining representative sections with the specific endothelial marker anti CD31 (clone JC/70A, isotope IgG1). A digital image analyser was used to measure the immunoreactivity. The following parameters were determined in the 'hot spots': vessel counts, vessel perimeter and endothelial stained area (expressed per mm2). The results were correlated with clinical and histopathological data. There was no significant relationship between the histopathological findings (tumour histology, tumour differentiation, FIGO stage, presence of lymph node metastasis or lymphovascular space involvement) and the median vessel count. In a univariate analysis all angiogenesis parameters had prognostic value: a higher vascularity was associated with worse prognosis (P < 0.05). Multiple regression analysis showed that vascular permeation (P < 0.001) and the median vessel count (P = 0.005) were the most important prognostic indicators. In the future these criteria may be used for selection of patients for anti-angiogenesis therapy.

Adult↗
PubMed1997

WT1 mutation in malignant mesothelioma and WT1 immunoreactivity in relation to p53 and growth factor receptor expression, cell-type transition, and prognosis.

The Wilms tumour 1 (WT1) gene is believed to contribute to the growth and differentiation of certain tissues, including mesothelium. This study assessed WT1 gene status by mutational screening in 42 malignant mesotheliomas (MMs) and 3 MM cell lines and detected two tumours with identical heterozygous single nucleotide deletions in intron 7, with no apparent consequence for WT1 function. Furthermore, the expression pattern of the WT1 gene was studied in MMs and related lesions using three anti-WT1 monoclonal antibodies (MAbs). Strong to moderate nuclear immunoreactivity was noted in MM in situ (54/56), cultured mesothelioma cells (4/5), and hyperplastic and normal pleural (non-neoplastic, NNM) specimens. WT1 immunoreactivity was absent in all primary tumours of lung and in pleural metastases from adenocarcinomas of breast and colon; immunoreactivity was present in pleural metastases from renal carcinomas, melanomas, and papillary carcinomas of the ovary. Expression of the WT1 protein in MM was not correlated with survival. Coordinate expression of the WT1 protein and its putative transcriptional target genes was determined by correlating WT1 immunostaining with epidermal growth factor receptor (EGF-R) and insulin-like growth factor 1 receptor (IGF-1R) expression on MM and NNM; no significant correlation was found, irrespective of p53 expression status. Finally, the putative involvement of WT1 in cell-type transition was supported by this study, in that epithelial mesothelioma showed the strongest WT1 immunoreactivity while sarcomatous mesothelioma showed the least.

Adult↗
PubMed1997

Evaluation of tumour angiogenesis as a prognostic marker in malignant mesothelioma.

Angiogenesis plays an important role in the growth, progression, and metastasis of solid tumours. Malignant mesothelioma (MM) of the pleura is a highly invasive tumour with a poor prognosis. In the present study, microvascular quantification was undertaken on 25 specimens of mesothelioma and 15 specimens of non-neoplastic mesothelium (NNM), by staining for the antigens CD34 and CD31. Areas of highest intratumoural microvascular density (IMD) were identified and counted either manually (mIMD) or on a computerized image analysis system (CIAS; iIMD). The two IMDs were significantly correlated with each other (r = 0.736; P < 0.001). The average IMD for MM was significantly (P < 0.001) higher than in NNM. Moreover, each unit increment in iIMD for MM, when regarded as a continuous variable, was significantly (P = 0.001) associated with an increased hazard of about 4 per cent. When regarded as a categorical variable, the patients in the highest tertile (> 58 vessels/field) had a significantly (P < 0.01; log-rank test) shorter survival than patients in the lowest tertile (< 45 vessels/field). This association was independent of the age of the patient and of the histological type or grade of the MM. No association was noted with p53 immunoexpression. Although the mean vascular area of blood vessels measured on the CIAS did not correlate with survival, assessment of IMDs can be an important independent prognostic indicator in malignant mesothelioma.

Antigens, CD34↗
PubMed1997

Prognostic value of bcl-2 expression in patients with operable carcinoma of the uterine cervix.

AIM: To evaluate the patterns of bcl-2 expression in early stage cervical carcinoma; to compare bcl-2 expression with clinicopathological findings; and to assess its prognostic value. METHODS: Wertheim radical hysterectomy specimens from 76 patients (FIGO stages Ia-IIb) with untreated nonmetastatic invasive cervical carcinoma were studied. Expression of bcl-2 was detected immunohistochemically using a monoclonal antibody. A tumour was regarded as positive when more than 5% of the neoplastic cells exhibited bcl-2 immunoreactivity. RESULTS: Forty eight (63%) cervical carcinomas were scored as bcl-2 positive and 28 (37%) as bcl-2 negative. Most tumours showed heterogeneous cytoplasmic staining. Bc1-2 immunoreactivity did not correlate with tumour histology, tumour stage, presence of lymph node metastases, or involvement of the lymphovascular space. The five year survival rate for patients with bc1-2 negative tumours was 34% and was 71% for patients with bc1-2 positive tumours. On multiple regression analysis (Cox proportional hazards model), bc1-2 expression and vascular permeation were independent predictors of overall survival. CONCLUSIONS: Bcl-2 expression seems to be associated with less aggressive behaviour in early stage cervical carcinoma. The transition to bcl-2 independence may play an important role in tumour progression.

Adult↗
PubMed1996

Glutathione S-transferase expression in malignant mesothelioma and non-neoplastic mesothelium: an immunohistochemical study.

Expression of the glutathione S-transferase (GST) subclasses alpha, mu and pi was investigated immunohistochemically in 20 normal or hyperplastic mesothelium and in 57 malignant mesothelioma cases. These results were correlated with survival and also with P-170 glycoprotein expression. Nearly all the non-neoplastic mesothelium cases were positive for GST alpha and pi. About half of the non-neoplastic cases were positive for mu. Twenty-nine (51%) malignant mesotheliomas were positive for at least one of the GST species; 21 (37%) showed immunoreactivity for alpha, 18 (31.5%) for mu and 21 (37%) for pi. A total of 54 mesothelioma cases displayed immunoreactivity for the P-170 glycoprotein. For GST pi and GST mu, a statistical significance between expression and increased survival was found (respectively P = 0.012 and 0.024) while for GST alpha no significance was found. The results of this study demonstrate that expression of GST pi correlates positively with increased survival in malignant mesothelioma. It is also concluded that, in mesothelioma, GST and P-170 glycoprotein may contribute to the resistance to cytotoxic drugs frequently observed in these tumours. No correlation between GST and P-170 expression was demonstrated.

Adult↗
PubMed1996

Evaluation and prognostic value of DNA content and of morphometric parameters in malignant mesothelioma using digital image analysis.

Fifty-seven cases of malignant mesothelioma were analyzed for nuclear diameter, DNA content and ploidy-related parameters, using Feulgen stained paraffin sections with a digital imaging analysis system. Thirty cases had a mean nuclear diameter > 7 microns and 31 cases were classified as near-diploid. A statistically significant correlation between survival and the mean nuclear diameter (P = 0.0006) and between survival and DNA index (P = 0.007) was obtained. For other DNA content parameters (proliferation index, 5c exceeding rate), only one of the two statistical tests showed a significant correlation with survival while the other test was of borderline significance. In this malignant mesothelioma population, the prognosis for patients with the epithelial type was better than for those with sarcomatous tumours (P = 0.01). In this population of patients, about half of the malignant mesotheliomas were aneuploid. The mean nuclear diameter, DNA index analysis and proliferation index analysis of the tumour cells on Feulgen stained paraffin sections can be used as independent prognostic parameters.

Cell Nucleus↗
PubMed1996

Second primary lung cancer in Flanders: frequency, clinical presentation, treatment and prognosis.

Patient and tumour characteristics of 23 patients presenting with a second primary lung cancer were analysed and compared with 534 patients with radically resected stage 1 non-small cell lung cancer (NSCLC). None of these characteristics is associated with a higher occurrence rate for second primary lung cancer. Prognosis in the latter patients is significantly worse than after resection of a 'solitary' NSCLC: the median survival time (MST) after resection of the first tumour is 50 months; after diagnosis of the second tumour only 14 months. Surgically retreated patients have a prognosis that is similar to that after resection of a 'solitary' NSCLC. No separate independent prognostic factors responsible for this survival difference could be isolated. Squamous histology and central location are associated with a longer recurrence free survival time. We conclude that the occurrence of a second primary lung cancer can not be predicted based on patient or tumour characteristics and that only surgical retreatment offers a chance of long survival in these patients.

Adult↗
PubMed1996

Ultraradical debulking of epithelial ovarian cancer with the ultrasonic surgical aspirator: a prospective randomized trial.

OBJECTIVE: Our purpose was to evaluate the effectiveness, benefits, and potential side effects of the use of the cavitational ultrasonic surgical aspirator for cytoreduction of advanced ovarian cancer. STUDY DESIGN: Forty patients with stage IIC to IV ovarian carcinoma were randomized to undergo ultraradical cytoreductive surgery with (group 1, 20 patients) or without (group 2, 20 patients) the use of the CUSA 200 cavitational ultrasonic surgical aspirator (Valleylab, Boulder, Colo). Preoperative and postoperative information and follow-up data were collected prospectively and compared between both groups. RESULTS: The amount of residual tumor after debulking surgery, the duration of the operation, and the rate of perioperative complications were comparable in both study groups. The amount of perioperative blood loss was significantly lower (1450 ml vs 1650 ml, p=0.02) in group 1. These patients had less morbidity (p<0.05), and could be discharged from the hospital significantly sooner (14 days vs 16 days, p=0.031). CA 125 levels 1 and 2 months after surgery were significantly lower in the group with cavitational ultrasonic surgical aspirator (p<0.01 and p<0.01, respectively), suggesting more successful cytoreduction. However, this is not reflected in a better disease-free or overall survival. CONCLUSION: Cavitational ultrasonic surgical aspirator-assisted cytoreductive surgery of advanced ovarian carcinoma is more effective in eradicating disease, reduces morbidity, and is cost beneficial.

Aged↗