Natriuretic peptides in pleural effusions: Beyond a diagnosis of heart failure

Our plain-English summary of Natriuretic peptides in pleural effusions: Beyond a diagnosis of heart failure, by J.M. Porcel (Respirology, 2020).

The study

• Author: J.M. Porcel
• Journal: Respirology
• Published: 2020;25(10):1021-1022
• Type of article: Editorial, Comment
• Cited by: 1 article, as counted by NIH iCite
• Read it: PubMed · Publisher

In plain English

This article was an editorial commentary, not a new study. It discussed a separate study by Tsolaki and colleagues, published in Respirology in 2020, on brain natriuretic peptide (BNP), a hormone usually measured to diagnose heart failure. The editorial did not discuss asbestos exposure. As the author described it, Tsolaki and colleagues found that fluid from laboratory cultures of mesothelioma cells, especially the epithelioid subtype, held significantly more BNP than benign mesothelial cell lines. They also reported that in patients with malignant mesothelioma, once heart failure had been reasonably excluded, BNP was disproportionately higher in pleural fluid than in blood. In a first cohort of 68 patients, a pleural fluid to blood BNP ratio of 2.11 or higher had a positive likelihood ratio of 17 (95% CI 5.57 to 51) for identifying mesothelioma. The author cautioned that each cohort had fewer than 15 mesothelioma patients, that other illnesses and medicines affect BNP levels, and that cell or tissue confirmation of cancer would still be needed. The author concluded that, if confirmed, the finding could help refine the difficult diagnosis of mesothelioma.

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: Editorial commentary on another published study (Tsolaki et al., Respirology 2020); no original data
• Who was studied: No study population of its own. The editorial described Tsolaki et al.'s laboratory work on mesothelioma and benign mesothelial cell lines and their two patient cohorts: 68 patients in a prospective cohort and 31 in a retrospective cohort, with fewer than 15 mesothelioma patients in each.
• Main results:
  • As reported by the author, Tsolaki et al. found that the fluid from mesothelioma cell cultures, particularly the epithelioid subtype, contained significantly more BNP than benign mesothelial cell lines.
  • As reported by the author, Tsolaki et al. found disproportionately higher BNP in pleural fluid than in plasma in patients with malignant mesothelioma, once heart failure had been reasonably excluded.
  • In Tsolaki et al.'s first prospective cohort of 68 patients, a pleural fluid to plasma BNP ratio of 2.11 or higher had a positive likelihood ratio of 17 (95% CI 5.57 to 51) and a negative likelihood ratio of 0.08 (95% CI 0.01 to 0.54) for identifying mesothelioma.
  • In Tsolaki et al.'s second retrospective cohort of 31 patients, at the best BNP ratio threshold of 2.42, the positive likelihood ratio was infinite (95% CI 2.1 to 501) and the negative likelihood ratio was 0.07 (95% CI 0.02 to 0.47).
  • The author interpreted these figures to mean that pleural fluid BNP at least double the blood level appears to be very strong evidence in favour of mesothelioma, while a ratio below 2 lowers the pre-test probability of the disease by more than 50%.
• The authors' conclusion: The author concluded that, despite its limitations, the Tsolaki et al. study raises questions about the role of natriuretic peptides in mesothelioma and, if confirmed in future clinical series, could help refine the difficult diagnosis of this tumour.
• Limitations the authors state:
  • The author noted that Tsolaki et al.'s sample was small, with fewer than 15 mesothelioma patients in each cohort.
  • The author noted that results could differ in real-world settings, where many patients would not meet the study's inclusion and exclusion criteria.
  • The author noted that BNP levels depend on the assay used and on other conditions, such as age, kidney problems, certain heart medicines and obesity.
  • The author noted that pleural effusions often have more than one cause, with heart failure frequently contributing.
  • The author noted that even if confirmed, the BNP ratio would not remove the need for cell or tissue confirmation of cancer.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Mesothelioma, Pleural plaques and thickening.

Medical terms in this study, explained in our Lexicon: Pleural Effusion.

Related studies

• Diffuse pleural thickening following heart failure-related pleural effusions in an asbestos exposed patient — M. Evison, P. Barber (2015)
• Occult primary cardiac lymphomas causing unexpected/sudden death or acute heart failure — A. De Martino, F. Del Re, et al. (2020)
• Malignant mesothelioma cells secrete natriuretic peptides: Data and diagnostic clinical implications — V. Tsolaki, S. Zarogiannis, et al. (2020)
• Elevated brain natriuretic peptide (BNP) is an early marker for patients at risk for complications after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS + HIPEC) — S.B. Fisher, S. Rafeeq, et al. (2018)
• Utility of hyaluronic acid in pleural fluid for differential diagnosis of pleural effusions: likelihood ratios for malignant mesothelioma — S. Atagi, M. Ogawara, et al. (1997)
• Pleural effusions and pneumothorax: Beyond simple plumbing: Expert opinions on knowledge gaps and essential next steps — R. Thomas, N.M. Rahman, et al. (2020)

Browse more research in Respirology, or return to medical research.