Pathological and molecular biological approaches to early mesothelioma

Our plain-English summary of Pathological and molecular biological approaches to early mesothelioma, by T. Tsujimura, I. Torii, A. Sato, et al (International Journal of Clinical Oncology, 2012).

The study

• Authors: T. Tsujimura, I. Torii, A. Sato, M. Song, K. Fukuoka, S. Hasegawa, T. Nakano
• Journal: International Journal of Clinical Oncology
• Published: 2012;17(1):40-7
• Type of article: Review
• Cited by: 17 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Malignant mesothelioma is an asbestos-related malignancy that arises primarily from mesothelial cells on the serosal surfaces of the pleural, peritoneal, and pericardial cavities. Malignant pleural mesothelioma (MPM) is most common, and its incidence is dramatically increasing worldwide as a result of widespread use of asbestos. Morphological discrimination between MPM and reactive mesothelial hyperplasia is difficult, and the most reliable pathological criterion for malignancy is mesothelial proliferation invading deeply into subpleural adipose tissues. To establish radical cure of MPM, it is crucial to find early-stage MPM of epithelial type, in which mesothelial proliferation is localized on the serosal surface of parietal pleura or limited within the submesothelial fibrous tissues of parietal pleura. The initial clinical presentation for patients with MPM is frequently dyspnea and/or chest pain due to large pleural effusion, and cytological analysis of pleural effusions is valuable to find patients with early-stage MPM of epithelial type. Recently, cytological features of MPM in pleural effusion, molecular markers for MPM, and genetic alternations of MPM have been reported. In this review, we discuss major issues on pathological and molecular biological approaches for diagnosis of early-stage MPM of epithelial type.

In plain English

This article was a review, not a new study. The authors discussed published work on diagnosing malignant pleural mesothelioma (MPM) of the epithelial type at an early stage. MPM was described as closely associated with asbestos exposure. The authors noted that it is very difficult to tell genuine invasion by MPM apart from benign, inflammation-related changes in mesothelial cells. They also noted that the most reliable sign of malignancy is mesothelial growth invading deeply into the fatty tissue under the pleura. They reviewed tissue features that point to malignancy, the appearance of cells in pleural fluid, staining markers and genetic changes. Citing another study, they reported that a FISH test found homozygous deletion (loss of both copies) of the p16INK4a/p14ARF gene region in 35 of 40 mesothelioma cases and in no cases of reactive mesothelial hyperplasia, a benign condition. The authors concluded that homozygous deletion of this gene region is generally accepted as a useful molecular marker for diagnosing MPM.

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: Review of published literature (no new data collected)
• Who was studied: No study population of its own. The review covered published pathology and molecular research on early-stage malignant pleural mesothelioma of the epithelial type.
• Exposure: Asbestos is mentioned only in general terms as associated with mesothelioma. No fiber types, products, jobs or doses were studied; the review concerns diagnosis.
• Main results:
  • The authors described distinguishing genuine invasion of MPM from benign, inflammation-induced infiltration and entrapment of mesothelial cells as very difficult.
  • The review stated that the most reliable pathological criterion for malignancy is mesothelial proliferation invading deeply into subpleural adipose (fatty) tissues.
  • Certain tissue features were described as indicative of malignancy even without invasion into the fatty tissue. These features were presented as useful for finding early-stage epithelial MPM.
  • The authors considered pleural effusion (fluid) cytology valuable for finding patients with early-stage epithelial MPM before a tumor mass can be detected clinically.
  • From a cited study: GLUT-1 staining was found in 40 of 40 mesothelioma cases, and all 40 cases of reactive mesothelial hyperplasia were negative.
  • From a cited study: FISH analysis found homozygous deletion of the p16INK4a/p14ARF locus in 35 of 40 mesothelioma cases (88%) and in no cases of reactive mesothelial hyperplasia.
  • From a cited study: 11 of 14 cases (79%) of epithelial-type mesothelioma showed deletions of the 3p21.1 region, which contains the BAP1 gene.
• The authors' conclusion: The authors concluded that homozygous deletion of the p16INK4a/p14ARF locus is generally accepted as a valuable molecular marker for diagnosing MPM.

Topics

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

Medical terms in this study, explained in our Lexicon: Mesothelioma, Malignant Mesothelioma, Mesothelial Cells, Serosal Surface, Pericardial, Pleural Mesothelioma, Reactive Mesothelial Hyperplasia, Parietal Pleura.

Related studies

• Practical approaches to diagnose and treat for T0 malignant pleural mesothelioma: a proposal for diagnostic total parietal pleurectomy — S. Hasegawa, N. Kondo, et al. (2012)
• Germline BAP1-positive patients: the dilemmas of cancer surveillance and a proposed interdisciplinary consensus monitoring strategy — P. Star, A. Goodwin, et al. (2018)
• Molecular characterization of localized pleural mesothelioma — Y.P. Hung, F. Dong, et al. (2020)
• Molecular Analysis of a Patient With Neurofibromatosis 2 (NF2) and Peritoneal Malignant Mesothelioma — C. Glass, L.M. Sholl, et al. (2020)
• Malignant Mesothelioma, BAP1 Immunohistochemistry, and VEGFA: Does BAP1 Have Potential for Early Diagnosis and Assessment of Prognosis? — E. Pulford, K. Huilgol, et al. (2017)
• Challenges and controversies in the diagnosis of malignant mesothelioma: Part 2. Malignant mesothelioma subtypes, pleural synovial sarcoma, molecular and prognostic aspects of mesothelioma, BAP1, aquaporin-1 and microRNA — D.W. Henderson, G. Reid, et al. (2013)

Browse more research in International Journal of Clinical Oncology, or return to medical research.