Unusual granular reactivity for carcinoembryonic antigen in malignant mesothelioma

Our plain-English summary of Unusual granular reactivity for carcinoembryonic antigen in malignant mesothelioma, by J.W. Stirling, D.W. Henderson, D.V. Spagnolo, et al (Human Pathology, 1990).

The study

• Authors: J.W. Stirling, D.W. Henderson, D.V. Spagnolo, D. Whitaker
• Journal: Human Pathology
• Published: 1990;21(6):678-9
• Cited by: 13 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Summary of the article

This letter to the editor, from pathologists at Flinders Medical Centre, South Australia, and Sir Charles Gairdner Hospital, Western Australia, described an unusual pattern of carcinoembryonic antigen (CEA) immunostaining in malignant mesothelioma. CEA is undetectable in most mesotheliomas and is commonly used to distinguish mesothelioma from adenocarcinoma. The authors reported that routine study of over 200 mesotheliomas with a polyclonal CEA antibody had supported this pattern. After they introduced a monoclonal CEA antibody, staining occurred in five of 45 consecutive mesotheliomas. All five showed focal to extensive coarsely granular cytoplasmic staining, often concentrated around the nucleus and of moderate to strong intensity. This staining was not seen with the polyclonal antibody. Three of the five also showed sporadic linear staining at the apical cell membrane, which was also seen with the polyclonal antibody. The tissues were two open pleural biopsies and three cell blocks from pleural effusions. Four tumours were epithelial and one was bimorphic. Immunoelectron microscopy in one case showed reaction product mainly associated with cytoplasmic vesicles, possibly Golgi-derived, and rough endoplasmic reticulum. One patient also had colon carcinoma, but all five pleural tumours had features highly characteristic of mesothelioma. The authors suggested that the antibody may recognise an epitope shared by CEA and other glycoproteins. They concluded that granular CEA immunostaining of this kind in no way invalidates a diagnosis of malignant mesothelioma.

PubMed has no abstract for this study, and the article doesn't print one. We wrote this summary from the full article with the help of AI. It is not the authors' wording.

In plain English

This was a letter to the editor from pathologists at two Australian hospitals. It described an unusual staining pattern seen when their laboratories began using a monoclonal antibody to carcinoembryonic antigen (CEA), a test used to help diagnose mesothelioma. Earlier routine work on over 200 mesotheliomas had used a polyclonal antibody. With the new monoclonal antibody, 5 of 45 consecutive mesotheliomas stained. All five showed coarsely granular staining inside the tumor cells, which the polyclonal antibody did not show. Three of the five also showed linear staining at the cell surface. The tissues were two open pleural biopsies and three samples of cells from pleural effusion fluid. Four tumors were epithelial and one was bimorphic. One patient also had colon carcinoma. In one case, electron microscopy linked the staining to small sacs inside the cells. The authors suggested the antibody might recognize a structure shared by CEA and other molecules. They said the work was still under investigation. The authors concluded that this granular staining in no way invalidates a diagnosis of malignant mesothelioma. The letter did not discuss asbestos exposure.

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: Letter to the editor describing laboratory observations in a small series of mesothelioma cases
• Who was studied: 45 consecutive mesotheliomas examined in the authors' laboratories (Flinders Medical Centre, South Australia, and Sir Charles Gairdner Hospital, Western Australia). Five of them stained and were described: two open pleural biopsies and three cell block sections from pleural effusion fluid. Over 200 mesotheliomas had earlier been studied routinely with a polyclonal antibody. Dates are not given.
• Exposure: No asbestos or other exposure was studied. The letter compared tissue staining with a monoclonal antibody to CEA (Biogenex) against a polyclonal antibody to CEA (Dakopatts).
• Main results:
  • With the monoclonal antibody, 5 of 45 consecutive mesotheliomas stained. All five showed coarsely granular staining in the cell cytoplasm. This pattern was not seen with the polyclonal antibody.
  • The granular pattern was not observed with the polyclonal antibody.
  • Three of the five cases showed sporadic linear staining along the apical cell membrane. The polyclonal antibody also showed focal staining in the same distribution in these cases.
  • In the one case examined by immunoelectron microscopy, the reaction product was mainly associated with cytoplasmic vesicles and rough endoplasmic reticulum, and it often surrounded lipid droplets.
  • Four of the five tumors were epithelial and one was bimorphic. One patient also had a colon carcinoma, but the authors stated that all five pleural tumors were highly characteristic of mesothelioma.
• The authors' conclusion: The authors concluded that granular immunostaining for CEA of the kind they described in no way invalidates a diagnosis of malignant mesothelioma.
• Limitations the authors state:
  • The authors stated that it is uncertain whether the monoclonal antibody reacts with blood group antigens.
  • The authors described the finding as still under investigation. They had not yet determined what the antibody recognizes, whether reactive (non-cancerous) mesothelial cells stain the same way, or whether other monoclonal CEA antibodies give similar staining.

Topics

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

Medical terms in this study, explained in our Lexicon: Carcinoembryonic Antigen (CEA), Malignant Mesothelioma, Mesothelioma, Adenocarcinoma, Monoclonal, Cell Block, Pleural Effusion, Carcinoma.

Related studies

• Differential reactivities of carcinoembryonic antigen (CEA) and CEA-related monoclonal and polyclonal antibodies in common epithelial malignancies — K. Sheahan, M.J. O'Brien, et al. (1990)
• Immunocytological staining reactions of anti-carcinoembryonic antigen, Ca, and anti-human milk fat globule monoclonal antibodies on benign and malignant exfoliated mesothelial cells — A.K. Ghosh, E.B. Butler (1987)
• Keratin proteins and carcinoembryonic antigen in lung carcinoma: an immunoperoxidase study of fifty-four cases, with ultrastructural correlations — J.W. Said, G. Nash, et al. (1983)
• Use of antibodies to carcinoembryonic antigen and human milk fat globule to distinguish carcinoma, mesothelioma, and reactive mesothelium — R.J. Marshall, A. Herbert, et al. (1984)
• Immunoperoxidase localization of keratin proteins, carcinoembryonic antigen, and factor VIII in adenomatoid tumors: evidence for a mesothelial derivation — J.W. Said, G. Nash, et al. (1982)
• Evaluation of pleural CYFRA 21-1 and carcinoembryonic antigen in the diagnosis of malignant pleural effusions — G. Salama, M. Miédougé, et al. (1998)

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