Pleural plaques and neoplasia in Finland

Our plain-English summary of Pleural plaques and neoplasia in Finland, by R. Kiviluoto, L.O. Meurman, M. Hakama (Annals of the New York Academy of Sciences, 1979).

The study

• Authors: R. Kiviluoto, L.O. Meurman, M. Hakama
• Journal: Annals of the New York Academy of Sciences
• Published: 1979;330:31-3
• Cited by: 17 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. 001033).

Summary of the article

The authors studied whether pleural plaques, which can be caused by asbestos, were linked with cancer in Finland, using two approaches. In the first, chest photofluorographs of 6000 adults from a 1962 mass x-ray survey in Tuusniemi commune were re-examined for calcified pleural plaques. Tuusniemi lies near two open asbestos mines at Paakkila, worked from 1918 to 1977. Plaques were found in 700 people. Controls without plaques came from Maaninka commune, where asbestos is not used in industry or present in soil. Cancers reported to the Finnish National Cancer Registry in 1962-77 were identified. There were 60 neoplasms in the plaque group and 53 among controls, including 13 and 14 lung cancers respectively. In the second approach, chest x-rays of 69 lung cancer cases recorded at Turku City Hospital in 1963-77 (after exclusions) and 69 age-matched controls were examined for pleural plaques and pulmonary fibrosis. Both plaques and fibrosis were present in 25 cases and 11 controls. Neither plaques nor fibrosis alone seemed linked with lung cancer, but the combination seemed to increase cancer risk 2.8-fold, which was statistically significant. The authors suggested that slight asbestos exposure causes plaques while heavy exposure leads to plaques and lung fibrosis. They considered the results in accord with the general view of the association between plaques and asbestos exposure.

PubMed has no abstract for this study, and the article doesn't print one. We wrote this summary from the full article with the help of AI. It is not the authors' wording.

In plain English

This short report described two Finnish studies of pleural plaques and cancer. First, the authors re-read 1962 mass-survey chest films of 6000 adults in Tuusniemi commune, near two open asbestos mines at Paakkila worked from 1918 to 1977, and found 700 people with calcified pleural plaques. They compared them with plaque-free controls from Maaninka commune, where no asbestos is used in industry or present in soil. Cancer registry records for 1962 to 1977 showed 60 cancers in the plaque group and 53 among controls, including 13 and 14 lung cancers; the number of controls was not stated. Second, 69 lung cancer patients X-rayed at Turku City Hospital in 1963 to 1977 were compared with 69 age-matched controls. Plaques alone or lung fibrosis alone did not seem linked with lung cancer, but both together seemed to raise the risk 2.8-fold, which the authors called statistically significant. The authors suggested that plaques may indicate slight asbestos exposure and plaques with fibrosis heavy exposure.

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: Two-part study: (1) follow-up through the Finnish National Cancer Registry of people with pleural plaques found in a 1962 mass x-ray survey, compared with plaque-free controls from another commune; (2) hospital-based comparison of lung cancer cases with age-matched controls for pleural plaques and lung fibrosis on chest x-rays
• Who was studied: Part 1: 6000 adults x-rayed in Tuusniemi commune in 1962, of whom 700 had calcified pleural plaques (series I), plus plaque-free controls from Maaninka commune (number not stated), followed for cancer 1962 to 1977. Part 2: 69 lung cancer cases from the x-ray department of Turku City Hospital, 1963 to 1977 (series II), and 69 age-matched controls from the x-ray file; mean age 65, two women in each group
• Exposure: Part 1: living near two open asbestos mines in Paakkila (Tuusniemi), worked 1918 to 1977; the fiber type is not named. Part 2: no direct exposure measure; pleural plaques and pulmonary fibrosis on chest x-ray were used as possible signs of asbestos exposure
• Main results:
  • Part 1: 60 cases of neoplasia were registered among the 700-person plaque group and 53 among the controls (control group size not stated)
  • Part 1: 13 lung cancers in the plaque group and 14 among the controls
  • Part 2: Neither plaques alone nor lung fibrosis alone seemed linked with lung cancer. Table 1 shows, for the 69 cancer cases versus the 69 controls: plaques but no fibrosis 7 vs 9; lung fibrosis but no plaques 8 vs 6; calcified plaques and lung fibrosis 25 vs 11; neither 29 vs 43
  • Part 2: Having both plaques and lung fibrosis seemed to increase lung cancer risk 2.8-fold, which the authors stated was statistically significant. No confidence interval or p-value was given. In the matched-pair table, 17 pairs had a case with both findings and a control with neither, and 6 pairs the reverse
  • The authors reported that lung cancer incidence was no higher in Tuusniemi (asbestos area) than in Maaninka (no asbestos) or in East Finland in general, and that the 700 plaque cases showed no association between pleural plaques and lung cancer
• The authors' conclusion: The authors considered that slight asbestos exposure may cause plaques, while heavy exposure may lead to plaques and lung fibrosis. On that assumption, they said, their findings were understandable and agreed with the general view of the association between plaques and asbestos dust exposure

Mines named here

Asbestos mines this study is about. Each mine's page says who ran it, when it worked, and what it produced.

• Paakkila mine, Finland

All asbestos mines

Topics

The National Library of Medicine indexes this study under subjects our site covers: Lung cancer, Pleural plaques and thickening.

Medical terms in this study, explained in our Lexicon: Pleural Plaques, Cancer Registry, Neoplasm, Lung Cancer, Chest X-Ray, Pulmonary Fibrosis, Fibrosis, Asbestos Exposure.

Related studies

• Incidence of cancer among anthophyllite asbestos miners in Finland — L.O. Meurman, E. Pukkala, et al. (1994)
• Lymphocytic alveolitis and pleural calcifications in nonoccupational asbestos exposure. Protection against neoplasia? — S.H. Constantopoulos, Y.A. Dalavanga, et al. (1992)
• Pleural fibrocalcific plaques and asbestos exposure — L.O. Meurman (1968)
• Pleural plaques and exposure to mineral fibres in a male urban necropsy population — A. Karjalainen, P.J. Karhunen, et al. (1994)
• Localized pleural plaques and lung cancer — T. Partanen, M. Nurminen, et al. (1992)
• Additional proteins in BAL fluid of Metsovites environmentally exposed to asbestos: more evidence of "protection" against neoplasia? — V. Galani, S. Constantopoulos, et al. (2002)

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