Evaluation of malignant mesothelioma in central Anatolia: a study of 67 cases

Our plain-English summary of Evaluation of malignant mesothelioma in central Anatolia: a study of 67 cases, by I. Gulmez, L. Kart, H. Buyukoglan, et al (Canadian Respiratory Journal, 2004).

The study

• Authors: I. Gulmez, L. Kart, H. Buyukoglan, O. Er, S. Balkanli, M. Ozesmi
• Journal: Canadian Respiratory Journal
• Published: 2004;11(4):287-90
• Cited by: 13 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: Malignant mesothelioma (MM) is a fatal neoplasm which frequently results from exposure to asbestos or erionite.

Method: Sixty-seven patients with MM were seen between 1990 and 2001. Their clinical and radiological features, as well as the therapy, were retrospectively evaluated.

Results: In 51 patients (76.1%), the MM was confined to the pleura, in 14 patients it was exclusively peritoneal and in two patients, it involved both areas. Of the 67 cases, 35 (52.2%) were women. The mean (+/- SD) age for all cases was 57.6+/-11.5 years. Dyspnea (67.2%), cough (55.2%) and chest pain (50.7%) were the most frequent symptoms of onset. Pleural effusion (92.4%) was the most common chest x-ray finding, whereas pleural effusion (60.8%), pleural nodules (34.7%) and pleural thickening (34.7%) were the most common computed tomography findings in pleural MM patients. The histological subtypes of MM were determined as epithelial in 60 patients (89.5%), sarcomatous in four patients (5.9%) and mixed in three patients (4.4%). Although 50.7% and 25.4% of the cases were exposed to erionite and asbestos, respectively, 23.9% of the cases recalled no exposure to asbestos or erionite. Exposures were environmental as opposed to occupational. Thirty-five patients (52.2%) were administered chemotherapy, and follow-up data were available for 22 patients. For these patients, the two-year survival rate was 22% and the two-year progression-free interval was 15.7%. There were no differences between patients with asbestos and erionite exposure.

Conclusion: MM should be considered when exudative pleural effusion is detected in a patient who has been exposed to asbestos or erionite. MM is a major public health problem in parts of Turkey and compulsory environmental control of fibrous mineral should be considered.

In plain English

This was a retrospective review of the records of 67 patients with malignant mesothelioma seen at the Department of Pulmonary Medicine of Erciyes University in Kayseri, Turkey, between 1990 and 2001. The authors classified exposure by where patients lived. Thirty-four patients (50.7%) came from three villages with erionite, a natural fibrous mineral found in volcanic rock. Seventeen (25.4%) came from asbestos villages, and 16 (23.9%) from regions with no known asbestos or erionite deposits. Fifty-one patients had pleural mesothelioma alone, 14 had peritoneal mesothelioma alone and two had both. Thirty-five patients were women. In patients from contaminated communities, exposure began at birth or early childhood, and the mean time from first exposure to evaluation was 45 years. Most tumours (60 patients) were of the epithelial type. Of 35 patients given chemotherapy, response data were available for 22. None had a complete remission, and their two-year survival rate was 22%. The authors concluded that mesothelioma in central Anatolia is caused by environmental, not occupational, exposure, and that finding fibre sources and preventing exposure is the most important issue. They noted that their exposure data were probably underestimated.

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: Retrospective review of hospital patient records (case series)
• Who was studied: 67 patients with malignant mesothelioma (32 men, 35 women) seen at Erciyes University, Kayseri, central Anatolia, Turkey, 1990 to 2001. The hospital serves a population made up largely of farmers from nearby erionite and asbestos regions.
• Exposure: Environmental (non-occupational) exposure to erionite or asbestos, assigned by the patient's village of residence. Exposure began at birth or early childhood in patients from contaminated communities. The median exposure duration was 27 years (range 12 to 56 years). The article does not identify the asbestos fibre type for individual patients. Its introduction says the asbestos in the region is mostly tremolite or 'chrysolite' (as printed), and that villagers used asbestos-contaminated 'white soil' as whitewash, plaster and baby powder substitute.
• Main results:
  • Of the 67 patients, 34 (50.7%) were from the three erionite villages, 17 (25.4%) were from asbestos villages, and 16 (23.9%) were from regions with no known asbestos or erionite deposits.
  • 51 patients (76.1%) had pleural mesothelioma alone, 14 had peritoneal mesothelioma alone, and 2 had both. All peritoneal mesothelioma patients were male.
  • The male-to-female ratio was 0.9 across all patients. Seventeen patients (25.4%) were aged 20 to 49 years.
  • In patients from contaminated communities, the mean latency period (from first exposure to evaluation) was 45 years, with a range of 24 to 73 years.
  • Histological type: epithelial in 60 patients (89.5%), sarcomatous in 4 (5.9%) and mixed in 3 (4.4%).
  • On chest x-ray, among 53 pleural mesothelioma patients, 49 (92.4%) had unilateral pleural fluid and 5 (9.4%) had pleural calcification.
  • 35 patients received chemotherapy, and response data were available for 22 of them. There were no complete remissions. In these patients, estimated overall survival was 12 months (plus or minus 3.8), progression-free survival was 9 months (plus or minus 3.1), the two-year survival rate was 22%, and the two-year progression-free interval was 15.7%.
• The authors' conclusion: The authors concluded that mesothelioma is a major health problem in Turkey and that in central Anatolia it is common and caused by environmental rather than occupational exposure. They found its outcome similar to that reported elsewhere, and they considered identifying sources of asbestos and erionite fibres and preventing further exposure the most important issue.
• Limitations the authors state:
  • The authors state that their exposure data are probably underestimated, because air quality was not systematically measured and exposure was equated with the patient's village of residence.
  • Most cases had no information on pathological tumour-node-metastasis staging.
  • There were no survival data for the patients treated with pleurodesis or pleurectomy/decortication.

Topics

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

Medical terms in this study, explained in our Lexicon: Malignant Mesothelioma, Neoplasm, erionite, Pleura, Dyspnea, Pleural Effusion, Chest X-Ray, Pleural Thickening.

Related studies

• Asbestos knowledge and awareness level in central part of Anatolia — S. Metintas, G. Ak, et al. (2017)
• High incidence of lung cancer and malignant mesothelioma linked to erionite fibre exposure in a rural community in Central Mexico — M.A. Ortega-Guerrero, G. Carrasco-Núñez, et al. (2015)
• An outbreak of pleural mesothelioma and chronic fibrosing pleurisy in the village of Karain/Urgüp in Anatolia — Y.I. Baris, A.A. Sahin, et al. (1978)
• Environmental malignant mesothelioma in southern Anatolia: a study of fifty cases — E.H. Zeren, D. Gümürdülü, et al. (2000)
• Lung cancer and mesothelioma in towns with environmental exposure to asbestos in Eastern Anatolia — H.C. Hasanoglu, Z. Yildirim, et al. (2006)
• Trouble in Anatolia — N.R. Anthonisen (2004)

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