Evaluation of AgNOR count in distinguishing benign from malignant mesothelial cells in pleural fluids

Our plain-English summary of Evaluation of AgNOR count in distinguishing benign from malignant mesothelial cells in pleural fluids, by M. Colecchia, O. Leopardi (Pathology, Research and Practice, 1992).

The study

• Authors: M. Colecchia, O. Leopardi
• Journal: Pathology, Research and Practice
• Published: 1992;188(4-5):541-4
• Cited by: 5 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

The authors have evaluated in eight reactive and eight malignant pleural effusions the number of intranuclear dots representing the nucleolar associated proteins stained with silver colloid technique (interphase nucleolar organizer regions-AgNORs). The mean number per nucleus in benign reactive effusions was 1.56 (SD 0.77) while in mesotheliomatous effusions it was 2.81 (SD 1.44). The statistical analysis of values, by Mann-Whitney U Wilcoxon Rank Sum W Test, revealed a significant difference of AgNOR counts in the two cytological samples. The variability of AgNOR areas and morphologies in reactive and mesotheliomatous nuclei in pleural fluids is evaluated applying automatic image analysis.

In plain English

This laboratory study from the Department of Pathology at Ospedale Maggiore in Lodi, Italy, tested whether a silver stain could help tell harmless (reactive) mesothelial cells from mesothelioma cells in fluid drained from around the lungs (pleural effusions). The stain marks small dots in the cell nucleus called AgNORs. The authors examined sixteen pleural effusions: eight from mesothelioma and eight benign inflammatory effusions. They counted dots in 50 nuclei per case and measured dot areas with computer-assisted image analysis. On average, the mesothelioma cells had more dots per nucleus, 2.81 (plus or minus 1.44), than the reactive cells, 1.56 (plus or minus 0.77). The authors reported this difference as statistically significant. However, the average values for individual cases overlapped between the two groups. The authors said this overlap makes judging a single case difficult. Their mesothelioma counts were lower than those in an earlier study, and they noted that dot-counting criteria are not uniform. The authors concluded that computer-assisted image analysis is useful for standardizing the method. The article does not discuss asbestos or any exposure history.

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: Laboratory diagnostic comparison of stained cell samples (pathology study using computer-assisted image analysis)
• Who was studied: Sixteen pleural effusion samples (eight from mesothelioma, eight benign inflammatory/reactive), retrieved as paraffin-embedded cell blocks from Surgical Pathology at Ospedale Maggiore di Lodi, Italy; dates of collection not given
• Main results:
  • Mean AgNOR dots per nucleus were 1.56 (plus or minus 0.77) in reactive effusions and 2.81 (plus or minus 1.44) in mesotheliomas; 50 nuclei were counted per case
  • The difference between the reactive and mesothelioma groups was reported as statistically significant by the Mann-Whitney test (two-tailed p of 0.00001)
  • Individual case averages overlapped between the mesothelioma and reactive groups
  • The distribution of AgNOR areas in reactive effusions showed two peaks, one at 8 pixels and one slightly above 20 pixels
• The authors' conclusion: The authors held that computer-assisted image analysis, rather than older optical counting criteria, is useful for standardizing the AgNOR silver staining method. They also said that group averages for mesothelioma and reactive cells are distinct, but that analysing a single case is difficult because of overlap.
• Limitations the authors state:
  • Because the two groups overlapped, analysing a single case is difficult
  • Dot-counting criteria are not uniform between studies; the authors' mesothelioma values differed from an earlier study's, which they attributed to differences in preparation, sample source and counting criteria

Topics

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

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

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