Peritoneal cystic mesothelioma: an electron microscopic and immunohistochemical study of two male patients

Our plain-English summary of Peritoneal cystic mesothelioma: an electron microscopic and immunohistochemical study of two male patients, by I.K. Sienkowski, A.J. Russell, S.A. Dilly, et al (Journal of Clinical Pathology, 1986).

The study

• Authors: I.K. Sienkowski, A.J. Russell, S.A. Dilly, B. Djazaeri
• Journal: Journal of Clinical Pathology
• Published: 1986;39(4):440-5
• Type of article: Case report
• Cited by: 37 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

The clinical, pathological, and ultrastructural features of two cases of peritoneal cystic mesothelioma occurring in men were studied. The results of immunohistochemical staining for CAM 5.2, epithelial membrane antigen, carcinoembryonic antigen, and Factor VIII related antigen are reported for the first time and compared with the staining results of two peritoneal cystic lymphangiomas. Although resembling cystic lymphangioma by light microscopy, cystic mesothelioma may have a greater tendency for local recurrence. Staining for CAM 5.2 or epithelial membrane antigen may facilitate the differentiation of these two entities.

In plain English

This was a report of two men with peritoneal cystic mesothelioma, a rare cystic tumour of the lining of the abdomen and pelvis. The first, aged 35, was admitted in November 1984 with nine months of increasing abdominal swelling. No history of asbestos exposure was obtained. A multicystic mass weighing 5.8 kg was removed, with no recurrence after six months. The second, aged 45, was admitted in December 1981 with lower abdominal pain and urinary symptoms. Removal was incomplete, but after three years there was no clinical evidence of recurrence. The article gives no asbestos history for this patient. Under the electron microscope, cells lining the cysts in both tumours had features characteristic of mesothelium. Both tumours stained strongly for CAM 5.2 and epithelial membrane antigen. Two peritoneal cystic lymphangiomas, a look-alike lesion, stained negative with all antisera. Citing earlier work, the authors wrote that there is no evidence of a causal relationship to asbestos. They concluded that these two stains may help diagnosis, while noting the stains were applied to only two cases.

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: Case report of two patients, with light microscopy, electron microscopy and immunohistochemical staining; staining results compared with two peritoneal cystic lymphangiomas
• Who was studied: Two men with peritoneal cystic mesothelioma treated at hospitals in Surrey, England. Case 1 was a 35-year-old man admitted in November 1984. Case 2 was a 45-year-old man admitted in December 1981. Sections of two peritoneal cystic lymphangiomas were stained for comparison.
• Exposure: No fiber type or dose was studied. For case 1, no history of asbestos exposure was obtained. The article does not state an asbestos history for case 2. In the discussion, citing earlier literature, the authors wrote that there is no evidence of a causal relationship between cystic mesothelioma and asbestos exposure.
• Main results:
  • Case 1: a very large multicystic mass filling the peritoneal cavity was removed as completely as possible and weighed 5.8 kg (printed '5-8 kg' in the scanned text). The patient had no recurrence after six months.
  • Case 2: tumour removal was incomplete. At three years of follow-up the patient was well with no clinical evidence of recurrence.
  • On light microscopy of both tumours, active pleomorphism, mitoses and infiltration were absent.
  • In both cases, electron microscopy showed that the cells lining the cysts had features characteristic of mesothelium.
  • Both cystic mesotheliomas stained strongly for CAM 5.2 and epithelial membrane antigen, faintly or equivocally for prekeratin, and negative for carcinoembryonic antigen.
  • In both cases the mesothelium stained negative for Factor VIII related antigen, while nearby blood vessel cells stained strongly positive.
  • The two comparison peritoneal cystic lymphangiomas stained negative with all antisera.
• The authors' conclusion: The authors concluded that staining for CAM 5.2 or epithelial membrane antigen may help diagnose cystic mesothelioma and tell it apart from cystic lymphangioma. They thought this may be especially useful in retrospective studies or when electron microscopy is unavailable.
• Limitations the authors state:
  • The immunohistochemistry was applied to only two cases.
  • The authors had not been able to examine a 'difficult' case in which the cyst lining looks exclusively endothelial on light microscopy.
  • The faint or equivocal keratin staining needs further investigation.

Topics

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

Medical terms in this study, explained in our Lexicon: Mesothelioma, Immunohistochemistry, Epithelial Membrane Antigen (EMA), Carcinoembryonic Antigen (CEA).

Related studies

• Immunohistological study of malignant diffuse mesotheliomas of the pleura — H. Loosli, J. Hurlimann (1984)
• Localized fibrous tumor of the serosal cavities. Immunohistochemical, electron-microscopic, and flow-cytometric DNA study — A.K. el-Naggar, J.Y. Ro, et al. (1989)
• The distinction of adenocarcinoma from malignant mesothelioma in cell blocks of effusions: the role of routine mucin histochemistry and immunohistochemical assessment of carcinoembryonic antigen, keratin proteins, epithelial membrane antigen, and milk fat globule-derived antigen — E.S. Cibas, J.M. Corson, et al. (1987)
• Cystic mesothelioma of the peritoneum. A report of three cases — S. Villaschi, F. Autelitano, et al. (1990)
• Solitary fibrous tumor of the pleura. An immunohistochemical, electron microscopic and tissue culture study of a tumor producing insulin-like growth factor I in a patient with hypoglycemia — E.H. Strøm, F. Skjørten, et al. (1991)
• A comparative immunohistochemical study of peritoneal and ovarian serous tumors, and mesotheliomas — N. Khoury, U. Raju, et al. (1990)

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