Epidemiology of mesothelial tumors in the London area

Our plain-English summary of Epidemiology of mesothelial tumors in the London area, by M.L. Newhouse, H. Thompson (Annals of the New York Academy of Sciences, 1965).

The study

• Authors: M.L. Newhouse, H. Thompson
• Journal: Annals of the New York Academy of Sciences
• Published: 1965;132(1):579-88
• Cited by: 41 articles, as counted by NIH iCite
• Read it: PubMed · Publisher
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 001535).

Abstract

Two groups of patients who have attended a large hospital in the East End of London have been examined to determine their exposure to asbestos. The first consisted of 83 patients in whom the diagnosis of mesothelioma had been confirmed at autopsy or by biopsy. In all but seven, past occupational and domestic histories were obtained. In 22 patients the tumor was peritoneal in origin, in 61 pleural. The earliest recorded death was 1917, but only 10 of the series died before 1950. Fifty-five per cent of the males and 42 per cent of the females died under the age of 55. The interval between first exposure and development of terminal illness ranged between 16 and 55 years (mean 37 years). The second group consisted of 76 patients of the same hospital, matched by sex and date of birth with those traced in the first series. Of the patients suffering from mesotheliomata 52.6 per cent had been exposed to asbestos, as compared to 11.8 per cent of the control series. The difference in the proportion of patients with known exposures in the two series is highly significant (χ2 = 29.1, P <.001). Three main types of exposure were recognized: work in factories manufacturing asbestos textiles, insulating materials, and other products; employment as laggers or insulators; and exposure to dust brought home by relatives working with asbestos. Eighteen of those employed in factory work and four whose relatives were working with asbestos were employed at one factory. This factory opened in 1913 and was, until recent years, a heavy user of crocidolite; all those whose records could be traced worked with this type of asbestos. Among the 36 patients with mesotheliomata, with no positive occupational history and no relatives living at home who worked with asbestos, there were 11 who lived within half a mile of an asbestos factory; five of the control series also lived in the same area. The difference in the proportion of patients in the two series is also statistically significant (χ2 = 7.85, P <.01).

PubMed has no abstract for this study. This is the authors' abstract, copied from the article.

In plain English

The authors studied 83 people with mesothelioma confirmed at the London Hospital over 50 years: 41 men (31 pleural, 10 peritoneal) and 42 women (25 pleural, 17 peritoneal); the article's summary says 61 pleural, 22 peritoneal. Histories came from hospital notes, family doctors, a large asbestos factory's records, and interviews, mostly with relatives. Controls were hospital in-patients matched by sex and birth period. Of 76 traced patients, 40 (52.6 per cent) had asbestos exposure, versus 9 (11.8 per cent) of 76 controls. All 17 patients from the large asbestos factory whose jobs were known had used crocidolite. Nine patients had relatives who worked with asbestos; usually the patient was a wife washing her husband's work clothes. Among people without work or household exposure, 11 of 36 patients and 5 of 67 controls had lived within half a mile of that factory, a statistically significant difference. The authors concluded there seemed little doubt of risk from occupational and domestic exposure; more evidence was needed on living near factories. They noted relatives' memories may have been incomplete.

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: Hospital-based series of confirmed mesothelioma cases compared with a matched control series of hospital in-patients (case-control comparison of asbestos exposure histories)
• Who was studied: 83 patients with mesothelioma confirmed at the London Hospital from specimens held over the past 50 years (earliest death 1917). The Introduction gives 41 men (31 pleural, 10 peritoneal) and 42 women (25 pleural, 17 peritoneal), but the article's Summary gives 61 pleural and 22 peritoneal. Histories were obtained for 76. There were 76 controls drawn from medical and surgical in-patients in early summer 1964, including six older men from a neighboring geriatric hospital.
• Exposure: Occupational, household and neighborhood asbestos exposure. This included work at a large asbestos factory making textiles, insulating materials and other goods, which used crocidolite with small amounts of chrysotile, and amosite from 1926. It also included work at other asbestos factories (asbestos types mostly unknown), work as laggers or heating engineers, dust brought home by relatives, and living within half a mile of the large factory.
• Main results:
  • Of 76 traced mesothelioma patients, 40 (52.6 per cent) had a history of asbestos exposure, compared with 9 (11.8 per cent) of the control series. The authors reported this difference as statistically highly significant (chi-square 27.11, P less than .001).
  • 18 mesothelioma patients (9 men, 9 women) had worked at the large asbestos factory. Of the 17 whose jobs were known, all had used crocidolite asbestos. For the other asbestos factories, the asbestos types were not known except for one woman who worked with crocidolite.
  • Nine mesothelioma patients (seven women, two men) had relatives who worked with asbestos. The most usual history was a patient who was a wife washing her asbestos-working husband's work clothes. The two men had, as boys of eight or nine, sisters working at the asbestos factory.
  • The heating engineers and laggers in the mesothelioma series were all men. Five had worked in dockyards on ship repairs, one in a power station, and one installing hospital sterilizing equipment.
  • All of these heating engineers and laggers had done this type of work for more than 20 years, but their exposure to asbestos was intermittent.
  • Among those with no occupational or domestic exposure, 11 of 36 mesothelioma patients (30.6 per cent) and 5 of 67 controls had lived within half a mile of the large factory at its present or previous site. The authors reported this difference as statistically significant (chi-square 7.85, P less than .01).
  • Including those who lived near the factory, 51 mesothelioma patients had been exposed. The interval between first exposure and onset of symptoms ranged from 16 to 55 years (mean 37.5). Duration of exposure ranged from five weeks to over 50 years.
  • Among the men, exposure was mostly industrial: 22 worked in asbestos factories or as laggers, two were exposed at home, and one lived near the factory. Among the women, 10 worked in asbestos factories, seven were exposed at home, and 10 lived near asbestos factories.
  • The authors found no evidence that patients with peritoneal tumors had different types of exposure from those with pleural tumors. A higher proportion of women had peritoneal tumors, but this difference was not statistically significant.
  • Half of the patients with pleural mesothelioma died within one year of symptom onset, a further third within two years, and only one survived more than three years. Of the patients with peritoneal tumors, 14 died within six months of symptom onset.
• The authors' conclusion: The authors concluded that there seemed little doubt of the risk from both occupational and domestic exposure to asbestos. They said more evidence was needed on risk to people living near asbestos factories or dockyards. They suggested that tumors after less than a year's exposure point to personal factors, and called for whole-population studies to evaluate dose-response.
• Limitations the authors state:
  • Histories for patients came mainly from surviving relatives, whose memory may have been defective or who may not have known of short exposures in the patient's youth.
  • Controls were interviewed in person rather than through relatives, so their histories were easier to obtain in detail and accurately than those of the mesothelioma patients.
  • No history could be obtained for seven mesothelioma patients, most of whom died before 1950.
  • Some of the 25 traced patients with no exposure found may have lived near other asbestos factories in London.
  • Family doctors' notes were often destroyed after the patient's death, so many doctors could not give information.

Topics

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

Medical terms in this study, explained in our Lexicon: Epidemiology, Mesothelioma, Autopsy, Biopsy, Asbestos Textiles, Insulator, Crocidolite, Occupational History.

Related studies

• Mesothelioma of pleura and peritoneum following exposure to asbestos in the London area — M.L. Newhouse, H. Thompson (1965)
• Mesothelioma in the London area — M.L. Newhouse (1991)
• Epidemiology of primary malignant mesothelial tumors in Canada — A.D. McDonald, A. Harper, et al. (1970)
• Mortality from all cancers of asbestos factory workers in east London 1933-80 — G. Berry, M.L. Newhouse, et al. (2000)
• Correlation between fibre content of the lung and disease in east London asbestos factory workers — J.C. Wagner, M.L. Newhouse, et al. (1988)
• Mortality of factory workers in east London 1933-80 — M.L. Newhouse, G. Berry, et al. (1985)

Browse more research in Annals of the New York Academy of Sciences, or return to medical research.