(1/953) The European mesothelioma epidemic.
Projections for the period 1995-2029 suggest that the number of men dying from mesothelioma in Western Europe each year will almost double over the next 20 years, from 5000 in 1998 to about 9000 around 2018, and then decline, with a total of about a quarter of a million deaths over the next 35 years. The highest risk will be suffered by men born around 1945-50, of whom about 1 in 150 will die of mesothelioma. Asbestos use in Western Europe remained high until 1980, and substantial quantities are still used in several European countries. These projections are based on the fit of a simple age and birth cohort model to male pleural cancer mortality from 1970 to 1989 for six countries (Britain, France, Germany, Italy, The Netherlands and Switzerland) which together account for three-quarters of the population of Western Europe. The model was tested by comparing observed and predicted numbers of deaths for the period 1990-94. The ratio of mesothelioma to recorded pleural cancer mortality has been 1.6:1 in Britain but was assumed to be 1:1 in other countries. (+info)
(2/953) Telomerase activity in human pleural mesothelioma.
BACKGROUND: Gradual telomere erosion eventually limits the replicative life span of somatic cells and is regarded as an ultimate tumour suppressor mechanism, eliminating cells that have accumulated genetic alterations. Telomerase, which has been found in over 85% of human cancers, elongates telomeres and may be required for tumorigenesis by the process of immortalisation. Malignant mesothelioma is an incurable malignancy with a poor prognosis. The disease becomes symptomatic decades after exposure to carcinogenic asbestos fibres, suggesting the long term survival of pre-malignant cell clones. This study investigated the presence of telomerase in pleural malignant mesothelioma, which may be the target for future anti-telomerase drugs. METHODS: Telomerase activity was semiquantitatively measured in extracts from 22 primary pleural mesotheliomas, two benign solitary fibrous tumours of the pleura, four mesothelioma cell lines, and six short term mesothelial cell cultures from normal pleura using a non-isotopic dilution assay of the telomeric repeat amplification protocol. RESULTS: Twenty of the 22 primary mesotheliomas (91%) and all tumour derived mesothelioma cell lines were telomerase positive. Different levels of enzyme activity were observed in the tumours of different histological subtypes. Telomerase activity could not be detected in the six normal mesothelial cell cultures or in the two mesotheliomas. Both benign solitary fibrous tumours showed strong telomerase activity. CONCLUSIONS: Telomerase activity is found in a high proportion of mesotheliomas and anti-telomerase drugs might therefore be useful clinically. The results are consistent with the hypothesis that telomerase activity may be a feature of carcinogenesis in mesotheliomas and possibly in many other cancers. (+info)
(3/953) Invasive thymoma with long-term survival by extensive reoperation.
The recurrence of invasive thymoma is often observed; however, no accepted treatment of recurrent invasive thymoma has yet been established. We herein report a 41-year-old woman with invasive thymoma and pleural dissemination who demonstrated long-term survival after undergoing 4 operations. Based on our findings, reoperation is thus suggested in patients with intrathoracic recurrence and long-term survival can be expected. (+info)
(4/953) Phase I trial of methotrexate-albumin in a weekly intravenous bolus regimen in cancer patients. Phase I Study Group of the Association for Medical Oncology of the German Cancer Society.
Methotrexate-albumin conjugate (MTX-HSA) is a novel human albumin-based prodrug conjugate of methotrexate (MTX). A low MTX loading rate provided optimal tumor targeting and therapeutic efficacy during preclinical testing. The objectives of this first Phase I study of MTX-HSA were to determine dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) in a weekly regimen. Seventeen cancer patients who were no longer amenable to standard treatment were enrolled and were evaluable for DLT. Up to eight injections were performed in weekly intervals. Dose escalation was as follows: 20, 40, 50, and then 60 mg/m2 MTX-HSA (based on the amount of MTX bound to albumin). Additional MTX-HSA courses were feasible in case of tumor response. DLT (mainly stomatitis, Common Toxicity Criteria grade 3) occurred, beginning at the 50 mg/m2 dose level after repeated administrations; in one case, thrombocytopenia was dose-limiting. Two events of DLT occurred at the 60 mg/m2 dose level within the first two administrations. Mild anemia, transaminitis, and one case of skin toxicity were found. No significant leukopenia, nausea, renal toxicity, or other toxicities were observed. MTX-HSA was well tolerated. Drug accumulation occurred on the weekly schedule. The half-life of the drug was estimated to be up to 3 weeks. Tumor responses were seen in three patients: (a) a partial response was seen in one patient with renal cell carcinoma (response duration, 30 months, ongoing); (b) a minor response was seen in one patient with pleural mesothelioma (response duration, 31 months, ongoing); and (c) a minor response was seen in one patient with renal cell carcinoma (response duration, 14 months until progression). Poststudy treatment was administered at 2-4-week intervals. No signs of toxicity or drug accumulation were seen. Altered pharmacological properties of MTX-HSA such as plasma half-life, tumor targeting, or intracellular metabolism might have contributed to these responses. The MTD for weekly administration was 4 x 50 mg/m2 MTX-HSA during short-term treatment. A regimen with MTX-HSA injections of 50 mg/m2 every 2 weeks was recommended for a further clinical Phase I study. (+info)
(5/953) Malignant mesothelioma due to environmental exposure to erionite: follow-up of a Turkish emigrant cohort.
The incidence of malignant mesothelioma is extremely high in some Turkish villages where there is a low-level environmental exposure to erionite, a fibrous zeolite. The best known example is the village of Karain. However, since epidemiological studies are difficult to perform in Turkey, the incidence and the dose-response curve have not been thoroughly examined. A small cohort of immigrants from Karain who have lived in Sweden for many years were studied. Exposure data, i.e. the time residing in Karain, and hospital records including pathological diagnosis, were recorded. The cohort consisted of 162 people. During the observation time, 18 deaths occurred, 14 (78%) of which were due to malignant pleural mesothelioma. In addition, there were five patients with mesothelioma who were still alive, one of whom had a peritoneal mesothelioma. Thus, the risk of mesothelioma is 135-times and 1,336-times greater in males and females, respectively, than for the same sex and age groups in Sweden. The risk increased with duration of residence. (+info)
(6/953) Establishment of four new mesothelioma cell lines: characterization by ultrastructural and immunophenotypic analysis.
The aim of this study was to assess the biological characteristics of four new malignant mesothelioma (MM) cell lines. Since simian virus (SV)40 sequences have been recently detected in MM, SV40 large T antigen (Tag) expression was also analysed. MM cell lines were characterized by morphological, ultrastructural and cytogenetic analysis. Expression of Tag and of relevant MM markers was studied by immunocytochemistry, surface antigens by indirect immunofluorescence and immunomodulating cytokines by enzyme-linked immunosorbent assay (ELISA). The four MM cell lines, established from pleural effusions, showed a slow proliferation rate and pleomorphic changes during culture. Cell lines expressed vimentin, cytokeratins 8 and 18, and the mesothelial antigen recognized by HBME-1 monoclonal antibody, but not carcinoembryonic antigen. Surface human leukocyte antigen (HLA)-class I and intercellular adhesion molecule (ICAM)-1 molecules were present on all the cell lines. While HLA class II and CD86 were constitutively undetectable, HLA-class II was present after interferon (IFN)-gamma stimulation. All cell lines displayed abnormal karyotypes with chromosome 6 abnormalities. Transforming growth factor (TGF)-beta2 and interleukin (IL)-6 were constitutively secreted, while tumour necrosis factor (TNF)-alpha was secreted only in response to lipopolysaccharide. Intranuclear Tag was expressed in two cell lines. The persistence of large T antigen with human leukocyte antigen class I and intercellular adhesion molecule-1 positivity may point to large T antigen as a target for cytotoxic T-lymphocyte-based immunotherapy in some malignant mesothelioma patients. (+info)
(7/953) Asbestos related mortality in Northern Ireland: 1985-1994.
BACKGROUND: The association between Belfast and research into the hazardous effects of asbestos exposure goes back many years. This paper aims to update previous papers and review the burden of asbestos related disease in Northern Ireland today. METHODS: A study was carried out of all deaths in Northern Ireland between 1985 and 1994 inclusive, in which an asbestos related disease was mentioned anywhere on the death certificate. RESULTS: During this 10 year period, 527 asbestos related deaths were recorded; 88 per cent of these were in men. A total of 410 (77.8 per cent) were registered as the primary cause of death but only 405 (76.9 per cent) of cases were the subject of an autopsy. Standardized rates of pleural cancer in males have been increasing at 3.2 per cent per year though the trend was not significant. Lower rates in the last two years may herald the commencement of a decline. Deaths were clustered around the Belfast estuary, the site of Northern Ireland's shipbuilding industry. High proportional mortality ratios were demonstrated for occupations associated with the shipbuilding and construction industries. Evidence is presented that casts doubt on the attribution of peritoneal cancers in females to asbestos exposure. If lung cancers are included, there may be an average of 81 asbestos related deaths in Northern Ireland every year. CONCLUSION: Asbestos related diseases continue to extract a heavy burden of ill health in Northern Ireland today. There are some indications that the upward trend may be on the wane but confirmation of this will have to await further data. Measures to reduce exposure in the workplace to both asbestos and to tobacco smoke are the only means of reducing this burden. (+info)
(8/953) Percutaneous cervical cordotomy for the control of pain in patients with pleural mesothelioma.
BACKGROUND: Severe chest pain is common in mesothelioma. Percutaneous cervical cordotomy, which interrupts the spinothalamic tract at the C1/C2 level causing contralateral loss of pain sensation, is particularly appropriate in mesothelioma as the tumour is unilateral and systemic analgesia may be ineffective and is limited by harmful side effects. METHOD: A retrospective review was performed to determine the effectiveness and complication rate of this procedure. RESULTS: Fifty two patients were using opioids prior to cordotomy. The median daily dose of morphine before and after cordotomy was 100 mg (range 0-1000 mg) and 20 mg (range 0-520 mg), respectively (p < 0.001). Forty three patients (83%) had a reduction in pain such that their dose of opioid could be at least halved. Twenty patients (38%) were able to stop completely. Recurrence of pain requiring an increase in opioid medication was recorded in 18 patients at a median time of nine weeks (range 0.7-26 weeks). Four patients developed mild weakness, two had troublesome dysaesthesia. The median time from cordotomy to death was 13 weeks (range 0.3-52 weeks). Six early deaths within two weeks of cordotomy occurred early in the series and reflect postoperative chest infection and poor selection as the patients were in the terminal stages of mesothelioma. CONCLUSIONS: Percutaneous cervical cordotomy is successful in treating pain from mesothelioma. There was a low complication rate in this series. Referral to a unit experienced in cordotomy is recommended as soon as pain from chest wall invasion is suspected. (+info)