Epithelioid lesions of the serosa

Our plain-English summary of Epithelioid lesions of the serosa, by S. Anttila (Archives of Pathology & Laboratory Medicine, 2012).

The study

• Author: S. Anttila
• Journal: Archives of Pathology & Laboratory Medicine
• Published: 2012;136(3):241-52
• Type of article: Review
• Cited by: 5 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Context: Diagnosing epithelioid serosal lesions remains a challenge because numerous different processes-primary or secondary, benign or malignant-occur in body cavities, some of which are very rare.

Objectives: To review the newest literature and to describe the morphologic criteria and immunohistochemical markers that are useful for distinguishing epithelioid serosal lesions.

Data Sources: Previously published literature concentrating on the newest research findings. Earlier reviews are principally referred to for established diagnostic criteria.

Conclusions: Immunohistochemistry with a panel of antibodies has made the diagnosis of epithelioid serosal lesions very reliable. When deciding on antibodies used in differential diagnosis, it is important to consider tumor location, clinical and radiologic information, and morphologic features. Immunohistochemistry is less useful in the differential diagnosis of benign versus malignant mesothelial lesions. The diagnosis of benign versus malignant mesothelial proliferations still relies on the histologic criteria of invasion.

In plain English

This article was a review, not a new study. The author summarized published literature on how pathologists distinguish epithelioid lesions of the serosa, the linings of body cavities such as the pleura and peritoneum. It covered epithelioid malignant mesothelioma, cancers spreading to these linings, primary serous carcinoma of the peritoneum, benign mesothelial hyperplasia, and rare mesothelial tumors. Asbestos exposure was not studied. The author noted that mesothelioma incidence is still rising in most countries owing to asbestos use decades ago. The author described the staining percentages for diagnostic markers as only suggestive because they vary between studies. For telling benign from malignant growths, the most reliable sign was invasion, for example into parietal pleural fat. The review stated that no causal association between asbestos and well-differentiated papillary mesothelioma has been recognized, although two studies reported exposure in about half of patients. It also stated that whether asbestos is a cause of localized mesothelioma is not known. The author concluded that antibody panels have made diagnosis of these lesions very reliable, but that benign versus malignant mesothelial growths are still told apart by histologic signs of invasion.

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: Narrative review of published literature on diagnostic criteria and immunohistochemical markers
• Who was studied: No study population of its own. The review covered published studies of epithelioid lesions of the serosa: pleura, peritoneum, pericardium and tunica vaginalis testis.
• Exposure: Not studied. Asbestos is mentioned only as background: past use is given as the reason mesothelioma incidence is still increasing.
• Main results:
  • The International Mesothelioma Interest Group and others suggested that, in addition to typical morphology, at least 2 positive and 2 negative antibodies be required for a definite diagnosis of mesothelioma.
  • The author stated that the marker positivity percentages compiled in Tables 1 through 3 are only suggestive because they vary between studies.
  • For benign versus malignant mesothelial lesions, the author described invasion (for example into parietal pleural fat) as the most reliable criterion of malignancy.
  • A cited systematic review (King et al) found desmin and EMA the most useful markers for distinguishing benign from malignant mesothelial proliferations, with sensitivity and specificity above 74%.
  • A cited study (Chiosea et al) found 9p21 deletion by FISH in 67% of pleural and 25% of peritoneal mesotheliomas, and in none of 40 reactive pleural proliferations. The author stated that such newer markers still need to be confirmed in independent series.
  • No causal association between asbestos exposure and well-differentiated papillary mesothelioma has been recognized, although 2 cited studies reported asbestos exposure in about half of the patients.
  • In a cited study (Galateau-Salle et al), 11 pleural cases of well-differentiated papillary mesothelioma had average survival of 74 months (10-year survival 30.8%), compared with 9.9 months for 1248 patients with diffuse mesothelioma.
  • For localized malignant mesothelioma, the author stated that it is not known whether asbestos exposure is a cause, because the tumor is rare and many reported cases lack exposure information.
  • Immunohistochemistry is less useful for telling benign from malignant mesothelial lesions, and that diagnosis still relies on histologic criteria of invasion.
• The authors' conclusion: The author concluded that immunohistochemistry with a panel of antibodies has made diagnosis of epithelioid serosal lesions very reliable.
• Limitations the authors state:
  • The author noted that criteria for positive staining differ between the studies reviewed.
  • The author noted that staining results may vary between laboratories, for example because of differences in tissue processing.

Topics

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

Medical terms in this study, explained in our Lexicon: Epithelioid, Immunohistochemistry, Differential Diagnosis.

Related studies

• Lymphoproliferative conditions of the serosa — R. Attanoos (2012)
• Diffuse neoplasms of the pleural serosa — L. Cardinale, F. Ardissone, et al. (2013)
• The mesothelial cell — S.E. Mutsaers (2004)
• Immunocytochemical panel for the identification of malignant cells in serous effusions — K.V. Nance, J.F. Silverman (1991)
• Malignant mesothelioma of the tunica vaginalis — M. Kamiya, T. Eimoto (1990)
• Immunolocalization of nestin, mesothelin and epithelial membrane antigen (EMA) in developing and adult serous membranes and mesotheliomas — J. Petricevic, H. Punda, et al. (2012)

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