Serum levels of soluble mesothelin-related peptides in malignant and nonmalignant asbestos-related pleural disease: relation with past asbestos exposure

Our plain-English summary of Serum levels of soluble mesothelin-related peptides in malignant and nonmalignant asbestos-related pleural disease: relation with past asbestos exposure, by J.A. Rodríguez Portal, E. Rodríguez Becerra, D. Rodríguez Rodríguez, et al (Cancer Epidemiology, Biomarkers & Prevention, 2009).

The study

• Authors: J.A. Rodríguez Portal, E. Rodríguez Becerra, D. Rodríguez Rodríguez, I. Alfageme Michavila, A. Quero Martínez, C. Diego Roza, A. León Jiménez, I. Isidro Montes, P. Cebollero Rivas
• Journal: Cancer Epidemiology, Biomarkers & Prevention
• Published: 2009;18(2):646-50
• Cited by: 50 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: Malignant pleural mesothelioma (MPM) results from malignant transformation of mesothelial cells. Past asbestos exposure represents a major risk factor for MPM and other benign pleural disease. Soluble mesothelin-related peptides (SMRP) have been regarded as a promising serum biomarker for MPM. The aim of this study was to investigate serum levels of SMRP in malignant and nonmalignant asbestos-related pleural disease.

Patients: Four groups of patients were investigated: group 1 composed of 48 healthy subjects, group 2 composed of 177 patients with previous asbestos exposure and no pleural disease, group 3 composed of 36 patients with MPM, and group 4 composed of 101 patients with previous asbestos exposure and benign pleural disease. Serum SMRP levels were determined by ELISA.

Results: Serum SMRP levels were significantly higher among group 3 than the other three groups. There were no differences in SMRP concentrations between groups 2 and 4. Subjects exposed to asbestos had higher SMRP concentrations than normal control subjects regardless of the presence of pleural disease. The area under the receiver operating characteristic curve for SMRP values was 0.75 (95% confidence interval, 0.68-0.83). The SMRP level at 0.55 nmol/L/L was determined as the most optimal cutoff value with resulting sensitivity and specificity of 72% and 72% for the diagnosis of MPM.

Conclusions: These data attest to good diagnostic sensitivity and specificity of SMRP for the diagnosis of malignant mesothelioma. We have also shown that serum SMRP levels might serve as a marker of asbestos exposure.

In plain English

This multicenter cross-sectional study from Spain measured blood levels of soluble mesothelin-related peptides (SMRP) in four groups. These were 48 unexposed healthy people, 177 asbestos-exposed people without pleural disease, 101 asbestos-exposed people with benign pleural disease, and 36 patients with malignant pleural mesothelioma. The two exposed groups without mesothelioma had to have at least 1 year of exposure, in industries including shipyards, insulation, building and asbestos cement. Exposure details were reported for only 15 of the 36 mesothelioma patients. Mesothelioma patients had higher SMRP (0.79 nmol/L) than the benign pleural disease group (0.40), exposed people without pleural disease (0.41) and controls (0.23), all statistically significant. The two exposed groups did not differ (P = 0.69), but both exceeded controls. In separating mesothelioma from asbestos-exposed people, a 0.55 nmol/L cutoff gave 72% sensitivity and 72% specificity (area under the curve 0.75, 95% confidence interval 0.68-0.83). SMRP was not significantly correlated with years of exposure. The authors concluded that SMRP had good diagnostic sensitivity and specificity for mesothelioma and might serve as a marker of asbestos exposure. They noted the healthy controls were much younger and called for longitudinal studies.

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: Prospective, multicenter, cross-sectional study comparing a blood marker across four groups; some mesothelioma samples came from an existing serum bank
• Who was studied: 362 people at hospitals in Spain in four groups: 48 healthy comparison subjects without asbestos exposure (group 1), 177 asbestos-exposed people with no pleural disease (group 2), 36 patients with malignant pleural mesothelioma (group 3; 20 sampled prospectively from January 2006 to December 2007 and 16 from a serum bank), and 101 asbestos-exposed people with benign pleural disease (group 4)
• Exposure: Past asbestos exposure, measured as years of exposure and type of industry. Groups 2 and 4 were recruited through a consultancy service for asbestos-exposed workers and had to have at least 1 year of exposure. Industries listed were asbestos cement, shipyard, insulation, building and others. Mean duration was 12.8 years in group 2 and 17.9 years in group 4. In the mesothelioma group, exposure time and type were available for only 15 patients. No fiber types were named.
• Main results:
  • Mesothelioma patients (group 3) had higher serum SMRP (0.79 plus or minus 2.61 nmol/L) than exposed people with benign pleural disease (0.40 plus or minus 0.14 nmol/L), exposed people without pleural disease (0.41 plus or minus 0.15 nmol/L) and healthy controls (0.23 plus or minus 0.07 nmol/L); P less than 0.001 for each comparison
  • SMRP did not differ between asbestos-exposed people with and without benign pleural disease (P = 0.69). Both exposed groups had higher SMRP than healthy controls (P less than 0.001).
  • Sensitivity and specificity were estimated for distinguishing mesothelioma patients from people exposed to asbestos
  • For distinguishing mesothelioma, the area under the ROC curve was 0.75 (95% confidence interval 0.68-0.83). The best cutoff, 0.55 nmol/L, gave 72% sensitivity and 72% specificity.
  • In this study, a cutoff of 1.1 nmol/L would give 97.2% specificity but only 24% sensitivity for mesothelioma
  • The correlation between years of asbestos exposure and SMRP level was very poor (Spearman 0.194; P = 0.50)
  • Mean duration of exposure was longer in exposed people with benign pleural disease (17.9 years) than in those without (12.8 years; P less than 0.001)
• The authors' conclusion: The authors concluded that their data confirm good diagnostic sensitivity and specificity of SMRP for malignant mesothelioma and that SMRP might also serve as a marker of asbestos exposure. They called for further longitudinal studies of SMRP as a marker of mesothelioma development in exposed people.
• Limitations the authors state:
  • The healthy control group was much younger than the other three groups. The authors did not believe this was a major confounding factor.
  • The lack of difference between exposed people with and without benign pleural disease may reflect low study power and the long latency between exposure and damage
  • The study may not have been powered to detect a relation between years of exposure and SMRP; a longitudinal study is needed
  • Exposure time and type were incomplete in the mesothelioma group because some data were collected retrospectively. These data are given for only 15 of 36 patients.

Topics

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

Medical terms in this study, explained in our Lexicon: Soluble Mesothelin-Related Peptides (SMRP), Asbestos-Related Pleural Disease, Asbestos Exposure, Pleural Mesothelioma, Malignant Transformation, Mesothelial Cells, Biomarker, confidence interval.

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• Soluble mesothelin-related peptides (SMRP) - high stability of a potential tumor marker for mesothelioma — D.G. Weber, D. Taeger, et al. (2007)
• Soluble mesothelin-related peptides in the diagnosis of malignant pleural mesothelioma — A. Scherpereel, B. Grigoriu, et al. (2006)
• Soluble mesothelin-related peptides levels in patients with malignant mesothelioma — A. Franko, V. Dolzan, et al. (2012)
• Diagnostic value of soluble mesothelin-related peptides for malignant mesothelioma: a meta-analysis — L. Luo, H.Z. Shi, et al. (2010)

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