Malignant mesothelioma and central nervous system metastases. Report of two cases, pooled analysis, and systematic review

Our plain-English summary of Malignant mesothelioma and central nervous system metastases. Report of two cases, pooled analysis, and systematic review, by A.C. Miller, M. Miettinen, D.S. Schrump, et al (Annals of the American Thoracic Society, 2014).

The study

• Authors: A.C. Miller, M. Miettinen, D.S. Schrump, R. Hassan
• Journal: Annals of the American Thoracic Society
• Published: 2014;11(7):1075-81
• Type of article: Case report, Systematic review
• Cited by: 21 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Rationale: The incidence and patterns of metastatic disease to the central nervous system (CNS) from malignant mesothelioma are not well characterized.

Objectives: We describe the treatment of two cases of pleural mesothelioma with CNS metastases. We also report the results of a systematic review with pooled data analysis of CNS metastases from malignant mesothelioma.

Methods: PubMed, Scopus, EMBASE, and Web of Science were searched to identify relevant published studies. Inclusion criteria for the pooled analysis were any clinical or autopsy study in which patients had a confirmed histological diagnosis of malignant mesothelioma and CNS metastasis was identified by autopsy, clinical pathological specimen, or compelling radiographic imaging. Case reports were excluded from the pooled analysis but were incorporated into the discussion. One hundred forty-one potentially relevant references were identified. Seven studies including 655 patients were included in the pooled analysis. Ninety-seven additional cases were identified and incorporated into the discussion. A systematic review of the literature is provided with pooled data analysis.

Measurements And Main Results: CNS involvement of malignant mesothelioma may occur by hematogenous spread or by local extension. Some cases may represent tumor dedifferentiation to a more aggressive histologic subtype. Surgery or stereotactic therapies may play a role for select patients; however, rapid recurrence has been reported.

Conclusions: The prognostic significance of CNS disease is not well characterized. Clinicians should consider and identify CNS involvement in patients with new or evolving neurologic symptoms because early identification may allow for palliative intervention.

In plain English

This brief communication described two patients with pleural mesothelioma that spread to the brain and reviewed published reports of mesothelioma involving the central nervous system (brain and spinal cord). In the first patient, a 60-year-old man, the brain tumor had changed from the original epithelioid type to the sarcomatoid type. It did not respond to steroids and radiation, and he died in January 2013. In the second, a 59-year-old man, a small brain lesion was found on a scan done before entering a clinical trial. It was surgically removed, but a new lesion appeared 6 weeks later. Pooling seven autopsy studies covering 655 patients, all with pleural mesothelioma, the authors found metastases inside the skull (brain or meninges) in 18 (2.7%). Among 97 further published cases, 77 (79%) arose from pleural or pericardial disease, and none came from peritoneal mesothelioma. The authors said this absence may reflect selection bias. The study did not examine asbestos exposure. The authors concluded that the prognostic significance of central nervous system spread is not well characterized and that early identification may allow palliative treatment.

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 case reports plus a systematic literature review with a pooled analysis of seven autopsy studies (case reports were reviewed but not pooled)
• Who was studied: Two men (aged 60 and 59) with pleural malignant mesothelioma seen at the National Institutes of Health; 655 patients with primary pleural malignant mesothelioma from seven autopsy series; and 97 additional published cases of mesothelioma involving the central nervous system
• Exposure: Not studied. The article concerns spread of mesothelioma to the central nervous system, not its causes. Asbestos is mentioned only as background.
• Main results:
  • Patient 1: the brain lesion showed a change (dedifferentiation) from the original epithelioid pleural tumor to the sarcomatoid subtype, with loss of mesothelin staining
  • Patient 1: the brain lesions did not respond to corticosteroids and radiation (3,500 cGy); he chose hospice care and died in January 2013
  • Patient 2: after removal of a single 3- to 4-mm brain lesion, a new 5-mm lesion was seen 6 weeks after surgery
  • In the seven pooled autopsy studies, intracranial (brain and meningeal) metastases were found in 18 of 655 patients (2.7%)
  • Among the 97 published case reports, CNS metastases arose from pleural or pericardial disease in 77 (79%) and from tunica vaginalis testes in 3 (3%); 17 were not specified
  • No cases of primary peritoneal mesothelioma spreading to the central nervous system were found
  • Of the 59 reported cases with a specified primary tumor subtype, 31 were sarcomatoid, 14 biphasic and 14 epithelioid
  • Of 35 cases with histology reported for both the primary tumor and the CNS metastasis, six showed a less differentiated (2) or dedifferentiated sarcomatoid (4) subtype in the metastasis; the authors described this as roughly 11% of cases
• The authors' conclusion: The authors concluded that the prognostic significance of central nervous system disease is not well characterized. They stated that clinicians should look for CNS involvement in patients with new or changing neurologic symptoms, because early identification may allow palliative intervention.
• Limitations the authors state:
  • The absence of peritoneal mesothelioma cases spreading to the CNS may reflect selection bias
  • Differences between the studies prevented a formal meta-analysis
  • It is unclear whether the brain lesions found at autopsy significantly changed the clinical course

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: Malignant Mesothelioma, Meta-Analysis, Systematic Review, Pleural Mesothelioma, Autopsy, Metastasis, Hematogenous Spread, Histological Subtype.

Related studies

• Nervous system metastases from malignant mesothelioma — N.M. Martinez, I.T. Gavrilovic, et al. (2013)
• Parental occupational exposure and risk of childhood central nervous system tumors: a pooled analysis of case-control studies from Germany, France, and the UK — C. Huoi, A. Olsson, et al. (2014)
• Occupational exposure to unintentionally emitted nanoscale particles and risk of cancer: From lung to central nervous system - Results from three French case-control studies — G. Manangama, C. Gramond, et al. (2020)
• Response to chemotherapy of brain metastases from malignant pleural mesothelioma — M. Colleoni, G. Liessi, et al. (1996)
• Malignant mesothelioma with brain metastases — J.A. Kaye, A.M. Wang, et al. (1986)
• Brain metastases in malignant pleural mesothelioma. Case report and review of the literature — K.S. Sridhar, A.M. Hussein, et al. (1989)

Browse more research in Annals of the American Thoracic Society, or return to medical research.