Identifying malignant mesothelioma by a pathological survey using the São Paulo state hospital cancer registry, Brazil

Our plain-English summary of Identifying malignant mesothelioma by a pathological survey using the São Paulo state hospital cancer registry, Brazil, by F.D.C. Bernardi, E. Algranti, M. Dolhnikoff, et al (Jornal Brasileiro de Pneumologia, 2024).

The study

• Authors: F.D.C. Bernardi, E. Algranti, M. Dolhnikoff, C.A.L. Pinto, I.M. Oliveira, E.N.A.M. Coletta, E.C.A.D. Silva, A.J.F. Nunes, D.B. Veneziano, C.T.M. Luizaga, R.L. Lorenzi, D.R.M.E. Silva, T. Mauad
• Journal: Jornal Brasileiro de Pneumologia
• Published: 2024;50(2):e20230343
• Cited by: 2 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Objective: To review the pathological diagnosis of possible cases and/or hidden cases of malignant mesothelioma (MM) between 2000 and 2012 using the Hospital-Based Cancer Registry database in the state of São Paulo, Brazil.

Methods: Possible cases were retrieved by assessing the database. Inclusion criteria were being older than 30 years of age and having ICD-O-3 topography and morphology codes related to MM. A board of expert pathologists reviewed the pathology reports and requested paraffin blocks in cases that demanded revision. After staining with calretinin, D2-40, WT-1 (as positive MM markers) and Ber-EP4 and MOC31 (as negative MM markers), cases were divided and studied independently by a pair of pathologists to confirm or discard the diagnosis of MM.

Results: Our sample comprised 482 cases from 25 hospitals, and 130 needed further histological revision. We received 73 paraffin blocks with adequate material. After board analysis, there were 9 cases with a definitive diagnosis of MM, improving the diagnostic rate in 12%. Two cases of previously diagnosed MM were discarded by review.

Conclusions: Our results confirm that part of MM underdiagnosis and underreporting in Brazil is due to incomplete or mistaken pathological diagnosis.

In plain English

This retrospective study reviewed pathology for cases in São Paulo state's Hospital-Based Cancer Registry, Brazil, from 2000 to 2012. The authors looked for people older than 30 with tumors coded to the mediastinum, pleura, peritoneum or retroperitoneum and diagnoses that could be, or be confused with, malignant mesothelioma. They selected 716 cases from 25 public hospitals; 11 hospitals sent 482 pathology reports. Of these, 130 cases were chosen for re-examination, and 73 tissue blocks had adequate material. New sections were stained with a panel of markers, pairs of expert pathologists reviewed each case independently, and a board reached consensus on disagreements. Nine were confirmed as malignant mesothelioma (three new diagnoses, six confirmed by previously unperformed tests), all epithelioid. Fifty-eight were ruled out, including two previously diagnosed as mesothelioma; six stayed inconclusive. The authors reported a 12% increase in the diagnostic rate. They concluded that part of mesothelioma underdiagnosis in Brazil is due to incomplete or mistaken pathology. They had no clinical or radiological information. Material from 14 hospitals could not be obtained, which they said may underestimate hidden cases. Asbestos exposure was not studied.

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 pathology review (re-examination of tissue by an expert pathology board) of cases from a hospital cancer registry
• Who was studied: 716 registry cases from 25 public hospitals in São Paulo state, Brazil. All were older than 30 and diagnosed from 2000 to 2012. Each had a tumor coded to the mediastinum, pleura, peritoneum or retroperitoneum, and a diagnosis compatible with, or confusable with, malignant mesothelioma. Reports were received for 482 cases from 11 hospitals, and tissue was re-examined for 73.
• Exposure: Not studied. The authors had no clinical data, and no asbestos exposure information was collected for the cases.
• Main results:
  • Pathology reports were obtained for 482 cases from 11 hospitals, all from services reporting more than 20 cases.
  • Of the cases selected for review, 77 paraffin blocks were received, and 73 had adequate material.
  • Among the 73 reviewed cases, 9 were confirmed as malignant mesothelioma, 58 had the mesothelioma diagnosis discarded, and 6 remained inconclusive.
  • Of the 9 confirmed mesotheliomas, 3 were new diagnoses and 6 were confirmed by an immunohistochemistry panel not previously performed.
  • All confirmed mesothelioma cases had epithelioid morphology.
  • Two cases previously diagnosed as mesothelioma were discarded on review. One pleural case was judged to be a metastasis of an adenocarcinoma.
  • The authors reported that the review increased the mesothelioma diagnostic rate by 12%.
• The authors' conclusion: The authors concluded that part of the under-recognition and underreporting of malignant mesothelioma in Brazil is due to incomplete or mistaken pathological diagnosis.
• Limitations the authors state:
  • The study was retrospective.
  • There was no access to clinical or radiological information, which could have helped reach diagnoses.
  • Specimens could not be obtained from 14 hospitals, most of them (12) general non-specialized hospitals. The authors said this may have led to underestimating hidden mesothelioma cases.

Topics

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

Medical terms in this study, explained in our Lexicon: Mesothelioma, Cancer Registry, Pathology Report, Paraffin Block, Calretinin, Podoplanin (D2-40), Wilms Tumor 1 (WT-1), Ber-EP4.

Related studies

• Causes of death in former asbestos-cement workers in the state of São Paulo, Brazil — G.A. Fernandes, E. Algranti, et al. (2021)
• Mortality from pleural mesothelioma in Rio de Janeiro, Brazil, 1979-2000: estimation from death certificates, hospital records, and histopathologic assessments — G.A. Pinheiro, V.C. Antão, et al. (2003)
• First report on Cryptococcus neoformans in pigeon excreta from public and residential locations in the metropolitan area of Cuiabá, State of Mato Grosso, Brazil — D.T. Takahara, S. Lazéra Mdos, et al. (2013)
• Malignant mesothelioma: prognostic variables in a registry of 180 patients, the Dana-Farber Cancer Institute and Brigham and Women's Hospital experience over two decades, 1965-1985 — K. Antman, R. Shemin, et al. (1988)
• Mesothelioma and employment in massachusetts: analysis of cancer registry data 1988-2003 — C.R. Roelofs, G.J. Kernan, et al. (2013)
• Cancer mortality by country of birth and cancer type in Sweden: A 25-year registry-based cohort study — D.N. Tollosa, K. Zendehdel, et al. (2024)

Browse more research in Jornal Brasileiro de Pneumologia, or return to medical research.