Malignant mesothelioma of the pleura in Barrow-in-Furness

Our plain-English summary of Malignant mesothelioma of the pleura in Barrow-in-Furness, by J.R. Edge, S.L. Choudhury (Thorax, 1978).

The study

• Authors: J.R. Edge, S.L. Choudhury
• Journal: Thorax
• Published: 1978;33(1):26-30
• Cited by: 64 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 002117).

Abstract

Ffty cases of malignant pleural mesothelioma (47 men and 3 women) have been diagnosed during the period 1966-76 in Barrow-in-Furness, all of them histologically proved and accepted by the Pneumoconiosis Panel. At the time of writing only three survive. There was a history of industrial exposure to asbestos in all 47 men, who had worked in various trades in the shipyard, as had one of the women. One of the women was married to a shipyard plumber, who may have brought home asbestos dust on his clothes. Only one patient, a housewife, aged 28 at diagnosis, had no known asbestos contact. The asbestos content of the lungs has been measured in the last 20 cases, in 18 of whom it was found to be substantially greater than the accepted levels for the general population. In a small number studied by electron microscopy, the predominant fibre was crocidolite. A positive histological diagnosis was achieved in 39 subjects during life in the expectation of securing industrial compensation, but, in spite of this, less than half of the dependants are currently receiving payments. Metastases, though never clinically apparent, were frequent at necropsy.

In plain English

This paper described 50 people with malignant mesothelioma of the pleura (47 men and 3 women) diagnosed from 1966 to June 1976 in Barrow-in-Furness, a shipbuilding town. All 47 men had worked in shipyard trades, and only one was a lagger. One woman had worked in the shipyard, one was married to a shipyard plumber, and one, a housewife aged 28, had no known asbestos contact. First exposure came on average 42 years before diagnosis (range 20 to 62), and average survival after diagnosis was six months. Of 20 patients whose lungs were analysed, only two had fewer than 20 000 fibres per gram, a level the article called acceptable for people not exposed at work. In a separate electron microscope study, five of 10 mesothelioma lungs and six of 10 pleural plaque lungs held small amounts of amphibole asbestos, all but one being crocidolite. Metastases were found at necropsy in 25 of 47 patients. Only 21 patients or widows were then receiving compensation. The authors concluded that new cases continued undiminished.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Case series of all malignant pleural mesothelioma cases diagnosed locally over about 10 years, with pathology studies (lung fibre counts, asbestos bodies, and electron microscopy with a comparison of mesothelioma, pleural plaque and control lungs)
• Who was studied: 50 patients with malignant pleural mesothelioma (47 men, 3 women) diagnosed 1966 to June 1976 in Barrow-in-Furness, UK (population 64 000; shipbuilding employing some 7000 men). All were histologically proved and accepted by the Pneumoconiosis Panel. Electron microscopy used 30 separate necropsy lungs: 10 early mesothelioma cases, 10 people with pleural plaques who died of unrelated diseases, and 10 controls.
• Exposure: Asbestos exposure in shipyard trades, classed as continuous (7 patients), intermittent (34), varied (8) or none (1). Trades included joiners, electricians, plumbers, drillers, engineers, coppersmiths and labourers. One woman worked in the shipyard and one was married to a shipyard plumber who may have brought dust home on his clothes. The authors linked the exposure to crocidolite removed when captured German ships were refitted after the war.
• Main results:
  • Only one of the 50 patients worked in a recognised asbestos trade (lagging).
  • One patient, a housewife aged 28 at diagnosis, had no known asbestos contact.
  • The interval from first asbestos exposure to diagnosis ranged from 20 to 62 years, averaging 42 years.
  • Average survival from diagnosis to death was six months (range 1-37 months). At the time of writing only three patients survived.
  • A diagnosis acceptable for compensation was made during life in 39 of the 50 patients: 30 by pleural biopsy and 5 at thoracotomy, plus 4 by positive fluid cytology among the 15 diagnosed only at necropsy.
  • Tumour type was mixed in 24, tubopapillary in 15 and undifferentiated (sarcomatous) in 11.
  • In the last 26 patients, pleural fluid cytology and needle biopsy were both positive in 16. Biopsy alone was positive in 3, fluid alone in 4, and both were negative in 3.
  • In the last 20 cases, lung fibre counts were 35 000 to one million fibres per gram of dried lung in nine. In nine more they ran from one million to 35.4 million (printed '35-4 million'). Only two were below 20 000 per gram, described as an acceptable level for people not industrially exposed.
  • Under electron microscopy, five of the 10 mesothelioma lungs and six of the 10 pleural plaque lungs showed small amounts of amphibole asbestos, all but one being crocidolite. Two of the 10 control lungs contained crocidolite and two contained chrysotile.
  • Pleural plaques were seen on X-ray on the side opposite the tumour in 30 patients. At necropsy, plaques were present in 26 of the 47 examined.
  • Distant metastases were never recognised clinically, but metastases were found at necropsy in 25 of 47 patients.
  • The authors recognised no definite cases of primary peritoneal mesothelioma. In one case, both pleura and peritoneum were involved and the origin could not be determined.
  • Only 21 of the patients or their widows were receiving compensation, according to the local Department of Health and Social Security office.
  • After the series closed in June 1976, five more cases occurred in the second half of 1976 and six in the first half of 1977.
• The authors' conclusion: The authors concluded that new mesothelioma cases continued undiminished, at about one a month in a workforce of 7000. They saw little prospect of a reduction until some 40 years after crocidolite use is finally discontinued. They also concluded that pleural fluid cytology proved as useful as needle biopsy in this series, and that thoracotomy should not be used for diagnosis.
• Limitations the authors state:
  • No fibre was found in about half the electron microscopy specimens, which the authors attributed probably to the small volume of lung examined.
  • The authors could not explain the low compensation figure because the local office could not provide further information.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Mesothelioma.

Medical terms in this study, explained in our Lexicon: Mesothelioma, Pleura, Pleural Mesothelioma, Pneumoconiosis, Crocidolite, Autopsy.

Related studies

• Asbestos related disease in Barrow-in-Furness — J.R. Edge (1976)
• Malignant mesothelioma of the pleura: review of 123 patients — J. Brenner, P.P. Sordillo, et al. (1982)
• Mesotheliomas and secondary tumors of the pleura — K. Ellis, M. Wolff (1977)
• Phase-II study with the combination of cisplatin and doxorubicin in advanced malignant mesothelioma of the pleura — H. Henss, H.H. Fiebig, et al. (1988)
• Black spots concentrate oncogenic asbestos fibers in the parietal pleura. Thoracoscopic and mineralogic study — C. Boutin, P. Dumortier, et al. (1996)
• Asbestos and the pleura: a review — D.W. Cugell, D.W. Kamp (2004)

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