Malignant mesothelioma in the State of Qatar: A clinico-epidemiological study

Our plain-English summary of Malignant mesothelioma in the State of Qatar: A clinico-epidemiological study, by W.H. Ibrahim, N. Fituri, N.H. Abouzeid, et al (Qatar Medical Journal, 2026).

The study

• Authors: W.H. Ibrahim, N. Fituri, N.H. Abouzeid, S.A. Khasawneh, M. Elgara, M. Hussein, I.A. Bozom, R. Mohsen, H. Ghazouani
• Journal: Qatar Medical Journal
• Published: 2026;2026(1):7
• Read it: PubMed · Publisher · Free full text

Abstract

Background: Malignant mesothelioma (MM) is a potentially fatal cancer that originates from the mesothelial surfaces, predominantly the pleura. Asbestos is the principal risk factor with a long latency period between exposure and disease development. The objective of this study was to investigate the clinical and epidemiological characteristics of MM in the State of Qatar.

Methodology: This was a retrospective cohort study of all MM cases diagnosed in the State of Qatar during the period from January 1, 2015, to December 31, 2023. MM cases were identified from the Qatari National Cancer Registry Database and the Hamad Medical Corporation (HMC) Histopathology Database. Demographic, clinical, laboratory, radiologic, and survival data were collected from these two databases.

Results: Among the total 22 MM cases diagnosed during the study period, migrant Egyptians constituted 15/22 (68.2%). The mean age for the study population was 57.9 ± 9.2 years with an age-standardized incidence rate of 24.1 cases per 1,000,000 individuals per year. The epithelioid histologic type was the predominant type (16/19; 84.2%), and most patients (13/14; 92.9%) were diagnosed at an advanced disease stage. The median overall survival (OS) was 16 months. The 1-year OS rate was 60.67%, dropping to 20.22% over 3 years. Though the differences were not statistically significant, patients with epithelioid histology and those with left-sided tumors experienced better OS outcomes.

Conclusion: MM is predominantly a cancer of Egyptian migrants in the State of Qatar, with a comparable incidence to the international rates. Epithelioid histologic type is the most common type in the State of Qatar, and the majority of patients are diagnosed at an advanced disease stage. Despite a better OS rate compared to other countries, the prognosis of MM remains grave.

© 2026 Ibrahim, Fituri, Abouzeid, Khasawneh, Elgara, Hussein, et al., licensee HBKU Press.

In plain English

This retrospective study reviewed all malignant mesothelioma cases diagnosed in the State of Qatar from January 1, 2015, to December 31, 2023, using the national cancer registry and the Hamad Medical Corporation histopathology database. All 22 cases were pleural mesothelioma. Twenty (90.9%) were men, the mean age was 57.9 years, and 15 of 22 (68.2%) were Egyptian migrants. The age-standardized incidence rate was 24.1 cases per 1,000,000 individuals per year. Occupation was recorded for only 9 patients; the listed jobs included asbestos cement manufacturing, ship building and railroad repair. Of 19 patients with a recorded tumor type, 16 had epithelioid mesothelioma. Of 14 with a recorded stage, 13 had stage IV disease. Median overall survival was 16 months. The 1-year survival rate was 60.67% and the 3-year rate was 20.22%. Mean survival was longer with epithelioid and left-sided tumors, but these differences were not statistically significant. The authors concluded that mesothelioma in Qatar is mainly a cancer of Egyptian migrants, with an incidence comparable to international rates and a grave prognosis. They noted missing data and a small sample, which prevented study of asbestos exposure details.

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 study of all diagnosed cases (described in the abstract as a retrospective cohort study), using national registry and hospital pathology records
• Who was studied: All 22 malignant mesothelioma cases (all malignant pleural mesothelioma) diagnosed in the State of Qatar between January 1, 2015 and December 31, 2023, identified from the Qatari National Cancer Registry Database and the Hamad Medical Corporation Histopathology Database
• Exposure: Asbestos exposure was not studied in detail. Occupation was recorded for only 9 patients, one each in: accountant, asbestos cement manufacturing, desk job, driver, an entry listed only as 'Asbestos', lawyer, ship building, railroad repair and soldier. Smoking history was recorded for 20 patients.
• Main results:
  • Of the 22 patients, 20 (90.9%) were male
  • 15 of 22 patients (68.2%) were Egyptian migrants resident in Qatar
  • Age-standardized incidence rate in Qatar: 24.1 cases per 1,000,000 individuals per year
  • Among 19 patients with a recorded histologic type, 16 (84.2%) had epithelioid mesothelioma
  • Among 14 patients with a recorded stage, 13 (92.9%) were diagnosed at an advanced stage (stage IV)
  • Among the 20 patients with a recorded smoking history, 14 (70%) were smokers
  • Pleural effusion was seen on imaging in all 22 patients. Pleural plaques were seen in 1 of 22 (4.5%).
  • For all patients, median overall survival was 16 months and mean survival 9.14 months. The 1-year overall survival rate was 60.67% and the 3-year rate was 20.22%.
  • Mean survival was 10.38 months with epithelioid versus 5.83 months with non-epithelioid tumors (P = 0.809), and 12.88 months with left-sided versus 7.0 months with right-sided tumors (P = 0.473). These differences were not statistically significant. Age, nationality and smoking also showed no significant survival differences.
• The authors' conclusion: The authors concluded that malignant mesothelioma in Qatar is predominantly a cancer of Egyptian migrants, with an incidence comparable to international rates. They found that most patients had epithelioid tumors and were diagnosed at an advanced stage. Despite what they described as better survival than in other countries, they said the prognosis remains grave.
• Limitations the authors state:
  • The study was retrospective, with missing data, and the sample was small. This did not allow extensive study of risk factors, details of asbestos exposure, or treatment effects.
  • The authors cautioned that the better survival compared with other countries should be interpreted with caution because of the small sample size
  • The small sample size affected the statistical significance of the prognostic factors examined (age, histologic subtype, smoking status)

Topics

Medical terms in this study, explained in our Lexicon: Mesothelioma, Pleura, Latency, Cohort Study, Cancer Registry, Histopathology, Incidence, Epithelioid.

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