Malignant mesothelioma is an uncommon tumour usually attributable to asbestos exBackground -Malignant mesothelioma is posure, which is rising in incidence in the UK.1 a rare pleural tumour associated with asClinical and pathological features of malignant bestos exposure. The proportion of maligmesothelioma have been previously well denant mesothelioma unrelated to asbestos scribed. [2][3][4] In many published series, however, exposure, and any differentiating features numbers are small and complete clinical, ocbetween exposed and unexposed cases, are cupational, and pathological details have been not well described. This study describes oc-difficult to obtain. The proportion of tumours cupational, clinical, and pathological fea-not related to asbestos, survival with different tures in a large cohort of cases of malignant tumour subtypes, and features of non-asbestos mesothelioma from south east England.related tumours are also uncertain. This report Methods -All 272 cases from this region provides complete documentation of 272 cases were studied, either in life or after death where mesothelioma was the cause of death when necropsy examination suggested within a defined geographical area in the south malignant mesothelioma. Detailed in-east of England for the calendar year 1987. formation was gathered regarding the ocIn the UK a system of compensation for cupational history, clinical course, and occupational lung disease has existed since mode of death. Necropsies were performed 1931, 5 and a regional network of Pneumoin 98% of cases. Lung tissue was examined coniosis Panels (now called Medical Boarding Centres (MBCs)) assesses live and posthumous histologically to confirm the diagnosis, claims. The London MBC area covers all of subtype of tumour, presence or absence of the industrial south east. asbestosis and asbestos bodies.In England all deaths suspected of being due Results -Exposure to asbestos was docuto industrial disease must be reported to the mented in 87% of cases, while in the recoroner and a necropsy performed. Until April mainder, no asbestos exposure was found 1988 it was mandatory for coroners to refer all nor were asbestos bodies seen; 94.5% were cases of malignant mesothelioma to MBCs for pleural, 5.1% peritoneal, and 0.4% peri-special examination of the lungs. A report by cardial. Right sided tumours were more specialist physicians as to cause of death and common than left sided tumours (ratio presence or absence of an occupational lung 1.6:1). Patients usually presented with disease was then made to the coroner. breathlessness and chest pain, but 33%Although only cases where there was any presented with pleural effusion in the ab-suspicion of industrial causation were legally sence of chest pain. The mean (SD) time required to be reported to the coroner, in pracfrom first exposure to asbestos to sympMedical Boarding tice -because of compensation issues -almost features do not differentiate between as-causation had arisen.

Sixty-four subjects with asbestos-related diffuse pleural thickening attending the London Medical Boarding Centre for Respiratory Diseases (formerly, the Central Pneumoconiosis Panel) were studied to investigate symptomatology, lung function, and radiographic change over an average period of 8 to 9 yr. Chest pain was a common symptom, occurring in over half of the subjects. Approximately one-third of the subjects had a history of pleurisy or pleural effusion. Full long function, available in all cases, showed a highly significant decrement (p < 0.001) compared with predicted values in all variables except gas transfer coefficient (Kco) at initial presentation, consistent with a restrictive ventilatory defect. Longitudinal lung function, available over a mean period of 8.9 yr in 36 subjects, showed a significant decrement above that predicted in FEV1 and FVC only (p < 0.05). Decreases in other parameters were observed, although statistical significance was not achieved. Radiographic score increased with time but there was no correlation between change in lung function and increasing radiographic score, probably reflecting the initial severity of the disease in subjects studied. These observations confirm an initial decrement in lung function in diffuse pleural thickening which is followed by comparatively little change over time.