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INTRODUCTION: Mesothelioma is a malignant tumour of the pleura or peritoneum caused by asbestos. It is increasing in frequency and the prognosis remains grim, with average survival around 1 year. SOURCES OF DATA: Medical literature and personal experience. AREAS OF AGREEMENT: Amphibole fibres are far more potent than chrysotile in causing mesothelioma. AREAS OF CONTROVERSY: A minority view suggests that mesotheliomas in those exposed to chrysotile are caused only by tremolite (an amphibole) which contaminates chrysotile. There is a hypothesis, for which evidence is weakening, that Simian virus 40 may cause mesothelioma. GROWING POINTS: There is emerging evidence of genetic variation in susceptibility to fibre carcinogenesis. There are developments in treatment, particularly chemotherapy with pemetrexed and cisplatin which prolongs survival and helps symptoms. AREAS TIMELY FOR DEVELOPING RESEARCH: Targeted agents for treatment are under investigation and may improve the outlook. The role of radical and palliative surgery requires clarification.

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BACKGROUND: The combination of cisplatin and etoposide (PE) has been a standard treatment for patients with poor-prognosis small cell lung cancer (SCLC). This non-inferiority design trial aimed to determine whether the combination of gemcitabine and carboplatin (GC) results in similar survival but is less toxic with better quality of life. METHODS: Previously untreated patients with SCLC with extensive disease or limited stage with poor prognostic factors were randomly assigned to six 3-weekly cycles of GC or PE. RESULTS: 241 patients (121 GC, 120 PE) were recruited, of which 216 (90%) had died. There was no difference in overall survival (HR 1.01, 95% CI 0.77 to 1.32). Median survival with GC and PE was 8.0 and 8.1 months, respectively. Median progression-free survival was 5.9 months with GC and 6.3 months with PE. Grade 3 or 4 myelosuppressions were more frequent with GC (anaemia: 14% GC vs 2% PE; leucopenia: 32% GC vs 13% PE; thrombocytopenia: 22% GC vs 4% PE), but these were not associated with increased hospital admissions, infections or fatalities. Grade 2-3 alopecia (68% PE vs 17% GC) and nausea (43% PE vs 26% GC) were more frequent with PE. Patients given GC received more chemotherapy as outpatients (89% GC vs 66% PE of treatment cycles). In QoL questionnaires, more patients receiving PE reported being upset by hair loss (p = 0.004) and impaired cognitive functioning (p = 0.04). CONCLUSIONS: GC is as effective as PE in terms of overall survival and progression-free survival and has a toxicity profile more acceptable to patients. TRIAL REGISTRATION NUMBER: ISRCTN 39679215.

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Malignant pleural mesothelioma (MPM) is a highly chemoresistant cancer with a poor prognosis. Hypoxia is a specific property of solid tumours, contributes to low apoptotic potential, and can be selectively targeted by bioreductive drugs. Hypoxia-inducible factor 1alpha (HIF-1alpha) is a subunit of a heterodimeric transcription complex that regulates several genes associated with tumour progression and anti-apoptosis. In this study, we measured for the first time the expression of HIF-1alpha in MPM. Our results show that HIF-1alpha is commonly expressed in MPM but not in normal mesothelium, consistent with the presence of hypoxia. HIF-1alpha does not appear to predict survival; however, this study suggests that bioreductive drugs should be investigated in clinical trials of MPM.

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PURPOSE: The Big Lung Trial (BLT) was a large, pragmatic trial to evaluate the addition of chemotherapy to primary treatment (ie, surgery, radical radiotherapy, or supportive care) in non-small-cell lung cancer (NSCLC). In the supportive care group, there was a small but significant survival benefit in patients treated with chemotherapy compared with supportive care alone (no chemotherapy). A substudy was undertaken to evaluate the quality of life (QoL) implications of the treatment options. QoL was assessed using European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaires C30 (QLQ-C30) and LC17, and daily diary cards. PATIENTS AND METHODS: EORTC QLQ-C30 and LC17 were collected at 0, 6 to 8, 12, 18, and 24 weeks. Diary cards were completed during the first 12 weeks of the study. The primary end point was global QoL at 12 weeks. RESULTS: A total of 273 patients were randomly assigned: 138 to no chemotherapy and 135 to chemotherapy. There was no evidence of a large detrimental effect on QoL of chemotherapy. No statistically significant differences in global QoL or physical/emotional functioning, fatigue and dyspnea, and pain were detected at 12 weeks. Higher rates of palliative radiotherapy in the no chemotherapy arm may have lessened differences in QoL. Global QoL, role functioning, fatigue, appetite loss, and constipation were prognostic indicators of survival at 12 weeks. CONCLUSION: There were no important adverse effects of chemotherapy on QoL.

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PURPOSE: Gemcitabine-platinum combination activity has been clearly established in a number of phase II studies. It has also been compared against other combinations in many phase III trials. It is generally believed that all such regimens have an equivalent impact on survival. This meta-analysis aims to quantify the treatment effect of gemcitabine plus a platinum agent in the treatment of advanced NSCLC and compare the combination to other regimens used globally. DESIGN: Data from a total of 4556 patients from 13 randomized trials investigating gemcitabine in combination with a platinum agent versus any other platinum-containing regimen were included in a meta-analysis of time-to-event outcomes. RESULTS: A significant reduction in overall mortality in favor of gemcitabine-platinum regimens was observed, hazard ratio (HR) 0.90 (95% CI: 0.84-0.96) with an absolute benefit at 1 year of 3.9%. Median survival was 9.0 months for the gemcitabine-platinum regimens and 8.2 months for the comparator regimens. Sub-group analysis of the first- and second-generation platinum-based comparator regimens also indicated a significant benefit for gemcitabine-platinum regimens, HR 0.84 (CI: 0.71-0.9985). Analysis of third-generation agent plus platinum regimens showed a non-significant trend favoring gemcitabine-platinum regimens, HR 0.93 (CI: 0.86-1.01). There was a significant decrease in the risk of disease progression in favor of gemcitabine-platinum regimens, HR 0.88 (CI: 0.82-0.93). An absolute benefit of 4.2% at 1 year was estimated. Median progression-free survival was 5.1 months for gemcitabine-platinum regimens compared with 4.4 months for the comparator regimens. Sub-group analysis indicated a statistically significant progression-free survival benefit for patients assigned to gemcitabine-platinum treatment compared to first- and second-generation platinum regimens, HR 0.85 (CI: 0.77-0.94), and third-generation agent plus platinum regimens, HR 0.89 (CI: 0.82-0.96).

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PURPOSE: This phase III randomized trial compared two chemotherapy regimens, gemcitabine plus carboplatin and mitomycin, ifosfamide, and cisplatin, in chemotherapy-naive patients with advanced non-small-cell lung cancer (NSCLC). The regimens were compared with regard to effects on survival, response rates, toxicity, and quality of life. PATIENTS AND METHODS: Eligible patients had previously untreated stage IIIB or IV NSCLC suitable for cisplatin-based chemotherapy. Randomly assigned patients were to receive four cycles, each at 3-week intervals, of carboplatin area under the curve of 5 on day 1 plus gemcitabine 1,200 mg/m(2) on days 1 and 8 (GCa) or mitomycin 6 mg/m(2), ifosfamide 3g/m(2), and cisplatin 50 mg/m(2) on day 1 (MIC). RESULTS: Between February 1999 and August 2001, 422 patients (GCa, n = 212; MIC, n = 210) were randomly assigned in the United Kingdom. The majority of patients received the intended four cycles (GCa, 64%; MIC, 61%). There was a significant survival advantage for GCa compared with MIC (hazard ratio, 0.76; 95% CI, 0.61 to 0. 93; P = .008). Median survival was 10 months with GCa and 7.6 months with MIC (difference, 2.4 months; 95% CI, 1.0 to 4.0), and 1-year survival was 40% with GCa and 30% with MIC (difference, 10%; 95% CI, 3% to 18%). Overall response rates were similar (42% for GCa v 41% for MIC; P = .84). More thrombocytopenia occurred with GCa (P = .03), but this was not associated with increased hospital admission or fatality. GCa caused less nausea, vomiting, constipation, and alopecia and was associated with fewer admissions for administration and better quality of life. CONCLUSION: In patients with advanced NSCLC, GCa chemotherapy was shown to be a better-tolerated treatment that conferred a survival advantage over MIC.

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BACKGROUND: In 1995 a meta-analysis of randomised trials investigating the value of adding chemotherapy to primary treatment for non-small cell lung cancer (NSCLC) suggested a small survival benefit for cisplatin-based chemotherapy in each of the primary treatment settings. However, the meta-analysis included many small trials and trials with differing eligibility criteria and chemotherapy regimens. METHODS: The aim of the Big Lung Trial was to confirm the survival benefits seen in the meta-analysis and to assess quality of life and cost in the supportive care setting. A total of 725 patients were randomised to receive supportive care alone (n = 361) or supportive care plus cisplatin-based chemotherapy (n = 364). RESULTS: 65% of patients allocated chemotherapy (C) received all three cycles of treatment and a further 27% received one or two cycles. 74% of patients allocated no chemotherapy (NoC) received thoracic radiotherapy compared with 47% of the C group. Patients allocated C had a significantly better survival than those allocated NoC: HR 0.77 (95% CI 0.66 to 0.89, p = 0.0006), median survival 8.0 months for the C group v 5.7 months for the NoC group, a difference of 9 weeks. There were 19 (5%) treatment related deaths in the C group. There was no evidence that any subgroup benefited more or less from chemotherapy. No significant differences were observed between the two groups in terms of the pre-defined primary and secondary quality of life end points, although large negative effects of chemotherapy were ruled out. The regimens used proved to be cost effective, the extra cost of chemotherapy being offset by longer survival. CONCLUSIONS: The survival benefit seen in this trial was entirely consistent with the NSCLC meta-analysis and subsequent similarly designed large trials. The information on quality of life and cost should enable patients and their clinicians to make more informed treatment choices.

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OBJECTIVES: The non-small cell lung cancer (NSCLC) meta-analysis suggested a survival benefit for cisplatin-based chemotherapy when given in addition to surgery, radical radiotherapy or 'best supportive care'. However, it included many small trials and trials with differing eligibility criteria and chemotherapy regimens. The aim of the Big Lung Trial was therefore to run a large pragmatic trial to confirm the survival benefits seen in the meta-analysis. METHODS: In the surgery setting, a total of 381 patients were randomised to chemotherapy (C, 192 patients) or no chemotherapy (NoC, 189 patients). C was three 3-weekly cycles of cisplatin/vindesine, mitomycin/ifosfamide/cisplatin, mitomycin/vinblastine/cisplatin or vinorelbine/cisplatin. RESULTS: Chemotherapy was given before surgery in 3% of patients whilst 97% received adjuvant chemotherapy. Baseline characteristics were: median age 61 years, 69% male, 48% squamous cell, 93% WHO PS 0-1, 27% stage I, 38% stage II, and 34% stage III. Complete resection was achieved in approximately 95% of patients. In the C group, 13% received no chemotherapy, 21% one or two cycles, and 64% all three cycles of their prescribed chemotherapy (60% of the latter with no delays or modification). 30% had grade 3/4 toxicity, mainly haematological, nausea/vomiting and neutropenic fever, and six patients were reported as having a treatment-related death. 198 (52%) of patients have died, but there is currently no evidence of a benefit in overall survival to the C group: HR 1.02 (95% CI 0.77-1.35), P = 0.90). CONCLUSIONS: This trial has failed to observe a survival benefit with adjuvant chemotherapy following complete resection of stage I-III NSCLC. However, the hazard ratio and 95% confidence intervals are consistent with the previously reported meta-analysis and two large recently reported trials, which suggest a small survival benefit with cisplatin-based chemotherapy.

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BACKGROUND: The incidence of mesothelioma is rising rapidly in the UK. There is no generally accepted standard treatment. The BTS recommends active symptom control (ASC). It is not known whether chemotherapy in addition prolongs survival or provides worthwhile palliation with acceptable toxicity. Palliation as recorded by patients has been fully reported for only two regimens: mitomycin, vinblastine, and cisplatin (MVP), and vinorelbine (N). The BTS and collaborators planned to conduct a phase III randomised trial comparing ASC only, ASC+MVP, and ASC+N in 840 patients with survival as the primary outcome measure. The aim of the present study was to assess the acceptability of the trial design to patients and the suitability of two standard quality of life (QL) questionnaires for mesothelioma. METHODS: Collaborating centres registered all new patients with mesothelioma. Those eligible and giving informed consent completed EORTC QLQ-C30+LC13 and FACT-L QL questionnaires and were randomised between all three or any two of (1) ASC only, (2) ASC+4 cycles of MVP, and (3) ASC+12 weekly doses of N. RESULTS: During 1 year, 242 patients were registered of whom 109 (45%) were randomised (55% of the 197 eligible patients). Fifty two patients from 20 centres were randomised to an option including ASC only. This translates into a rate of 312 per year from 60 centres interested in collaborating in the phase III trial. The EORTC QL questionnaire was superior to FACT-L in terms of completeness of data and patient preference. Clinically relevant palliation was achieved with ASC. CONCLUSION: The planned phase III trial is feasible.

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OBJECTIVES: Our study aimed to determine the lung tissue concentration of asbestos and other mineral fibres by type and length in persons with mesothelioma aged 50 yr or less at time of diagnosis, compared to controls of similar age and geographical region. In this age group it was thought that most, but not all, work-related exposures would have been since 1970, when the importation of crocidolite, but not amosite, was virtually eliminated. METHODS: Eligible cases were sought from recent reports by chest physicians to the SWORD occupational disease surveillance scheme. Lung tissue samples were obtained at autopsy from 69 male and four female cases, and mineral fibres identified, sized and counted by electron microscopy. Fibre concentrations per microg dry tissue were compared with similar estimates from a control series of autopsies of sudden or accidental deaths. Unadjusted, and adjusted odds ratios calculated by logistic regression, assessed relative risk in relation to fibre type, length and concentration. RESULTS: Unadjusted and adjusted odds ratios increased steadily with concentration of crocidolite, amosite, tremolite and all amphiboles combined. There was also some increase with chrysotile, but well short of statistical significance. Incremental risk examined in a linear model was as highly significant for all amphiboles together as individually. Short, medium and long amphibole fibres were all associated with increased risk in relation to length. Mullite and iron fibres were significant predictors of mesothelioma when considered without adjustment for confounding by amphiboles, but, after adjustment, were weak and far from statistically significant. CONCLUSIONS: In this young age group, amosite and crocidolite fibres could account for about 80% of cases of mesothelioma, and tremolite for some 7%. The contribution of chrysotile, because of low biopersistence, cannot be reliably assessed at autopsy, but to the extent that tremolite is a valid marker, our results suggest that it was small. The steep linear trend in odds ratio shown by amphiboles combined indicates that their effects may be additive, with increased risk from the lowest detectable fibre level. Non-asbestos mineral fibres probably made no contribution to this disease. Contrary to expectation, however, some 90% of cases were in men who had started work before 1970; this was so whether or not amosite or crocidolite was found in lung tissue.

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OBJECTIVES: Our study aimed to identify occupations at increased risk of developing mesothelioma in persons aged 50 yr or less, and to relate these occupations to lung tissue concentration of asbestos fibres by type. In this age group it was thought that most, but not all, work-related exposures would have been since 1970, when the importation of crocidolite, but not amosite, was virtually eliminated. METHODS: Eligible cases were sought from recent reports by chest physicians to the SWORD occupational disease surveillance scheme. Work histories were obtained for 115 men and 13 women, usually with the help of the chest physicians or coroners. Jobs were coded by the Office of National Statistics, so that the observed years spent in each occupation could be compared with expected values from census data, 1960-90. Lung tissue samples were obtained at autopsy from 69 male and four female cases, and mineral fibres identified, sized and counted by electron microscopy. RESULTS: Of 37 industrial occupations analysed, odds ratios were significantly raised in eight: five in the construction industry and the others in shipbuilding, the manufacture of cement products and the manufacture of non-metallic mineral products (including asbestos). The concentrations in lung of crocidolite and amosite fibres, which together could account for 80-90% of cases, did not differ between occupational categories; those for amosite were appreciably higher than for crocidolite. Tremolite fibres were rarely found. CONCLUSION: Mesothelioma in this young age group is dominated by carpenters, plumbers, electricians and insulators in the construction industry, and is mainly attributable to amphibole exposure. Work in shipbuilding and manufacture of mineral products was less important than in earlier studies. Contrary to expectation, however, some 90% of cases were in men who had started work before 1970.

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BACKGROUND: To assess the response rate, toxicity and survival in patients with malignant pleural mesothelioma treated with liposomal daunorubicin. The study design allowed for dose escalation pending toxicity. PATIENTS AND METHODS: Liposomal daunorubicin (DaunoXome, Nexstar, USA) 120 mg/m2 was administered every 21 days to a maximum of 6 cycles. Patients had to have histologically-proven malignant pleural mesothelioma. Patients were all chemotherapy-naïve with ECOG performance status 0-2. RESULTS: Fourteen patients were enrolled. There were no objective or symptomatic responses though nine patients (64%) had stable disease on therapy. Myelosuppression was the major toxicity with 9 of 11 patients evaluable for toxicity experiencing grade 3 or 4 neutropenia. Other toxicities seen in at least 30% of patients included grade 3 infection and grade 2 nausea and vomiting. The median overall survival by intention-to-treat analysis was 6.1 months from the time of first treatment. The median duration of stable disease from time of first treatment for patients not progressing on therapy was 5.1 months. CONCLUSIONS: Liposomal daunorubicin 120 mg/m2 has no useful clinical activity in patients with malignant pleural mesothelioma. Toxicity was substantial with most patients experiencing at least one episode of grade 3 or 4 neutropenia. Liposomal daunorubicin cannot be recommended for patients with malignant pleural mesothelioma.

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A total of 29 previously untreated patients with histologically proven malignant pleural mesothelioma, with an ECOG score of < or = 2 and UICC stage I-II disease, were enrolled between May 1994 and October 1996. On days 1 and 2, 18 x 10(6) IU/day of rIL-2 was administered by continuous intravenous infusion, and 6 x 10(6) IU/day of rIL-2 by subcutaneous injection on days 5--20 inclusive of a 42-day cycle. Further treatment was administered if no radiological disease progression was demonstrated. A total of 29 patients were assessable for toxicity and 25 for response, and 49 cycles of IL-2 were administered with a median of one per patient (range, < 1-4). Toxicity included mild fever, nausea and vomiting, and skin rashes, < grade II. Three patients failed to complete one cycle of treatment because of toxicity and one died of disease before response evaluation. Two patients achieved a partial response (8%, 95% CI 1-26%) surviving 18.1 and 18.7 months from diagnosis. A total of 11 patients (44%, 95% CI 24-65%) with stable disease had a median survival of 13.6 months (range 6.5-33.8). The median survival was 8.6 months (range 3.7-34.5) for the 12 patients with progressive disease (48%, 95% CI 28-69%). This regimen of rIL-2 is well tolerated and shows limited activity in mesothelioma.

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PURPOSE: To evaluate the response rate and impact on quality of life of vinorelbine given as cycles of 30 mg/m(2) weekly for 6 weeks to patients with malignant pleural mesothelioma. PATIENTS AND METHODS: Twenty-nine patients with histologically proven malignant pleural mesothelioma were enrolled (26 male patients and three female patients; median age, 58 years [range, 29 to 77 years]). Seventeen patients had epithelioid tumors, two had sarcomatoid tumors, and 10 had biphasic tumors. The International Mesothelioma Interest Group staging system was used: one patient had stage Ib disease, 10 had stage II disease, eight had stage III disease, and 10 had stage IV disease. Patients were treated with weekly injections of vinorelbine 30 mg/m(2). A cycle consisted of six weekly injections. The new guidelines to evaluate the response to treatment in solid tumors were used. Responses were measured by spiral computed tomography scan. RESULTS: All twenty-nine patients had measurable disease and were assessed for response. There were seven partial responses (24% [95% confidence interval, 10% to 44%]), 16 patients had stable disease (55%), and six patients had disease progression on therapy (21%). The median number of vinorelbine injections was 12 (range, 2 to 30). Quality-of-life analyses showed a benefit for vinorelbine therapy. CONCLUSION: Vinorelbine shows promise in the palliation of patients with malignant pleural mesothelioma. The relatively low toxicity of the drug suggests that trials of vinorelbine in combination with other agents should be feasible.

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The nephrotic syndrome and membranous nephropathy is well recognized in association with solid tumors, although less is understood of the process that links them. We report a 27-year-old man presenting with the nephrotic syndrome and stage I membranous glomerulonephritis on biopsy. A bilar mass with regional lymphadenopathy was found simultaneously, the histology of which was shown to be an infiltrative atypical bronchial carcinoid tumor. The neoplasm was successfully treated with combined chemotherapy and radiotherapy, and over this period his nephrotic-range proteinuria resolved. As has been described with other malignancies, membranous nephropathy associated with a bronchial carcinoid tumor may resolve with treatment of the underlying condition.

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BACKGROUND: The entry of patients into randomised clinical trials (RCTs) in lung cancer is low. A study was undertaken to assess the reasons why patients with non-small cell lung cancer did not enter a trial involving randomisation to receive or not receive three courses of cisplatin based chemotherapy in addition to primary treatment by surgery, radiotherapy, or best supportive care. METHODS: The study was carried out in two large London institutions with a special interest in recruiting patients to lung cancer trials. Patients recently diagnosed as having non-small cell lung cancer were prospectively identified and followed to see whether they entered the RCT and, if not, to identify the main reasons why. RESULTS: Six hundred and eighty eight patients newly diagnosed with non-small cell lung cancer were identified between November 1995 and July 1998; 274 (39.8%) were deemed ineligible for the RCT for clinical reasons, most frequently their general condition rendering them unfit for chemotherapy. Another 161 (23.4%) were ineligible for logistical reasons-for example, they were discharged to centres not participating in the RCT or they were not considered for the trial at an appropriate time in their management. Of 253 potentially eligible patients, only 63 (24.9% of those eligible) agreed to enter the RCT and four entered another study. Of those who did not enter, 77 (41.4%) declined without stating a reason, 61 (32.8%) did not want chemotherapy, and only eight (4.3%) expressed a wish to have chemotherapy. CONCLUSIONS: Despite considerable time and effort, the proportion of patients recruited was small (9.2%). Many seen were ineligible but, of 253 potentially eligible patients, 186 (73.5%) refused to enter the RCT.

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PURPOSE: Chemotherapy for non-small-cell lung cancer (NSCLC) remains controversial. We describe the two largest reported, randomized, parallel trials designed to determine whether the addition of chemotherapy influences duration and quality of life in localized, unresectable (mitomycin, ifosfamide, cisplatin [MIC]1 trial) and extensive (MIC2 trial) disease. PATIENTS AND METHODS: Ambulatory patients with NSCLC, aged 75 years or younger, with localized disease, were randomized in MIC1 to receive up to four cycles of chemotherapy (CT: mitomycin 6 mg/m(2), ifosfamide 3 g/m(2), and cisplatin 50 mg/m(2)) every 21 days, followed by radical radiotherapy (CT + RT) or radiotherapy (RT) alone. Extensive-stage patients were randomized in MIC2 to identical chemotherapy plus palliative care (CT + PC) or palliative care (PC) alone. Short-term change in quality of life (QOL) was assessed in a subgroup of patients. Data from the two trials were combined to allow multivariate and stratified survival analyses. RESULTS: Seven hundred ninety-seven eligible patients were randomized, 446 in MIC1 and 351 in MIC2. MIC CT improved survival in both trials (significantly in MIC2). The median survival time in MIC1 was 11.7 months (CT + RT) versus 9.7 months (RT alone) (P =.14); whereas in MIC2, median survival time was 6.7 months (CT + PC) compared with 4. 8 months (PC alone) (P =.03). QOL, assessed in 134 patients from start of trial to week 6, showed improvement with chemotherapy and deterioration with standard treatment. In the combined analysis of 797 randomized patients, the positive effect of MIC on survival was significant overall (P =.01) and after adjusting for prognostic factors (P =.01). CONCLUSION: MIC chemotherapy prolongs survival in unresectable NSCLC without compromising QOL.

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BACKGROUND: An aetiological role for Simian virus 40 (SV40) in malignant mesothelioma has been suggested from studies in the USA and the UK but results have been conflicting. A study was undertaken to look for evidence of SV40 in stored tissue samples from pleural mesotheliomas. METHODS: DNA was extracted from paraffin embedded tissue. The presence of DNA was established by amplification of a 250 bp product from the betaglobin gene. Primers PYV.F and PYV.R were used in a concentration of 50 per mol each per reaction to amplify a 172 bp fragment of a conserved region of SV40 that codes for a portion of large T antigen that is common to SV40 and other polyoma viruses. RESULTS: Twelve of the 17 samples contained amplifiable betaglobin DNA. None of the samples (0/12, 95% CI 0 to 26.5%) was positive for the polyoma large T antigen. CONCLUSIONS: These results do not lend any support to the hypothesis that SV40 infection may be aetiologically relevant to the increasing incidence of mesothelioma in the UK.

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Lung cancers exhibit complex heterogeneous karyotypes and to date sequencing the serial somatic mutations which give rise to malignant change has proved difficult. Cigarette smoke causes a field change in the respiratory mucosa with mutations demonstrable even in histologically normal areas. After smoking cessation many of these mutations seem to persist indefinitely so that the risk of an ex-smoker developing lung cancer never reverts to that of a life-long non-smoker. Demonstration of specific somatic mutations in biopsy or sputum samples may eventually provide a useful method of screening for lung cancer. Somatic mutations give useful information about prognosis in non-small cell lung cancer and they are the key to exciting future retroviral and monoclonal antibody mediated therapies.

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