A case of pleural epithelioid sarcoma of proximal type presenting as malignant pleural mesothelioma

Our plain-English summary of A case of pleural epithelioid sarcoma of proximal type presenting as malignant pleural mesothelioma, by G.A. Madsen, T.R. Rasmussen, S. Bærentzen (Journal of Thoracic Oncology, 2013).

The study

• Authors: G.A. Madsen, T.R. Rasmussen, S. Bærentzen
• Journal: Journal of Thoracic Oncology
• Published: 2013;8(10):e89-90
• Type of article: Case report
• Cited by: 5 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Summary of the article

The authors reported a case of pleural epithelioid sarcoma of proximal type that presented as malignant pleural mesothelioma (MPM), seen at Aarhus University Hospital, Denmark. A 45-year-old man presented with one month of progressing dyspnea and right shoulder pain. He was a truck driver and a smoker of about 15 pack-years, with no history of asbestos exposure. A chest radiograph showed a large right pleural effusion, and 3300 ml of bloody fluid was drained; cytology showed no malignant cells. Computed tomography showed several irregular pleural plaques resembling MPM. Positron emission tomography–computed tomography showed increased 18F-fluorodeoxyglucose uptake in the right pleura and in mediastinal and retroperitoneal lymph nodes. Pleural biopsies taken at thoracoscopy showed tumor cells with rhabdoid characteristics. The tumor stained strongly for vimentin, pancytokeratin KL-1 and CK8, was positive for CD34, and showed loss of INI-1. It was negative for specific mesothelial markers, including calretinin, HBME1, nuclear WT-1 and D2-40. The findings were judged consistent with epithelioid sarcoma of proximal type rather than mesothelioma. The patient deteriorated rapidly and died in a hospice about two months later. A PubMed search found no other cases of primary pleural epithelioid sarcoma. The authors concluded that such tumors may in the past have been diagnosed as MPM. They stated that correct diagnosis matters because MPM and sarcomas are treated differently.

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 case report from Aarhus University Hospital, Denmark, described a 45-year-old man, a truck driver and smoker with no history of asbestos exposure, who had shortness of breath and right shoulder pain for one month. Doctors drained 3300 ml of bloody fluid from his right pleural cavity, and no malignant cells were found in it. Scans showed irregular pleural plaques resembling malignant pleural mesothelioma, with increased PET uptake in the right pleura and in lymph nodes of the mediastinum and retroperitoneum. Pleural biopsy stains were positive for vimentin, KL-1, CK8 and CD34, showed loss of INI-1, and were negative for the specific mesothelial markers tested. The authors judged the tumor to be a primary pleural epithelioid sarcoma of proximal type, not mesothelioma, and found no other such cases in a PubMed search. Two months after admission he entered a hospice and died within a week. The authors concluded that such tumors may previously have been diagnosed as mesothelioma, and that a correct diagnosis matters because the two are treated with different drugs.

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 (single patient)
• Who was studied: One 45-year-old man, a truck driver, treated at Aarhus University Hospital, Denmark
• Exposure: No history of asbestos exposure. He was a smoker with an estimated 15 pack-years and worked as a truck driver.
• Main results:
  • 3300 ml of bloody pleural fluid was drained from the right pleural cavity of this patient.
  • Cytology of the pleural fluid showed no malignant cells.
  • CT showed irregular pleural plaques resembling malignant pleural mesothelioma.
  • Pleural biopsy immunostains were positive for CD34 and showed loss of INI-1, along with strong positivity for vimentin, pancytokeratin KL-1 and CK8.
  • There was no reaction to the specific mesothelial markers calretinin, HBME1, nuclear WT-1 or D2-40.
  • The findings were judged consistent with epithelioid sarcoma of proximal type rather than mesothelioma.
  • A PubMed search by the authors found no other cases of primary pleural epithelioid sarcoma.
  • The patient deteriorated rapidly. Two months after admission he was admitted to a hospice and died within 1 week.
  • The authors stated that mesothelioma and sarcomas do not respond to the same treatment: cisplatin and pemetrexed are first-line for mesothelioma, and a different drug is first-line for sarcomas. They stated that a correct diagnosis is essential for choosing treatment.
• The authors' conclusion: The authors concluded that, with improved diagnostic tools such as immunohistochemistry, more pleural epithelioid sarcomas may be recognized, and that some such tumors might in the past have been diagnosed as malignant pleural mesothelioma.

Topics

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

Medical terms in this study, explained in our Lexicon: Epithelioid, Sarcoma, Pleural Mesothelioma, Dyspnea, Asbestos Exposure, Chest X-Ray, Pleural Effusion, Cytology.

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• Nuclear Brachyury Expression Is Consistent in Chordoma, Common in Germ Cell Tumors and Small Cell Carcinomas, and Rare in Other Carcinomas and Sarcomas: An Immunohistochemical Study of 5229 Cases — M. Miettinen, Z. Wang, et al. (2015)
• How useful is GLUT-1 in differentiating mesothelial hyperplasia and fibrosing pleuritis from epithelioid and sarcomatoid mesotheliomas? An international collaborative study — A.N. Husain, M.K. Mirza, et al. (2014)

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