Fine needle aspiration cytology of well-differentiated papillary mesothelioma: a case report

Our plain-English summary of Fine needle aspiration cytology of well-differentiated papillary mesothelioma: a case report, by Y. Gong, R. Ren, N.G. Ordóñez, et al (Acta Cytologica, 2005).

The study

• Authors: Y. Gong, R. Ren, N.G. Ordóñez, X. Sun, N. Sneige
• Journal: Acta Cytologica
• Published: 2005;49(5):537-42
• Type of article: Case report
• Cited by: 12 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: Well-differentiated papillary mesothelioma (WDPM) is an uncommon subtype of mesothelioma that typically occurs in the peritoneum of women without a history of asbestos exposure and usually follows an indolent clinical course. Fine needle aspiration (FNA) of this type of tumor has rarely been reported.

Case: A 64-year-old woman with 11-year history of colon cancer and an adrenal nodule was found, on abdominal computed tomography, to have a mass in the right lobe of the liver. Aspirates of the mass were composed of abundant, tight, papillary groups, monolayered, pavementlike sheets; and scattered single cells with minimal atypia. The cell block showed a predominantly papillary growth pattern and a single layer of bland, cuboidal to flattened covering cells with stout, fibrovascular cores containing clusters of foamy histiocytes. Tumor cells in the focal tubulopapillary and solid areas were mingled with inflammatory cells and showed slightly more atypia than did the cells covering the papillae. The differential diagnoses were intrahepatic papillary neoplasm, including well-differentiated mesothelioma and metastatic low grade papillary serous carcinoma. At surgery the tumor was found to be a pedunculated peritoneal mass that arose from the posterior surface of the right lobe of the liver. The mesothelial origin of the tumor was confirmed by both immunoperoxidase study and electron microscopic examination, which demonstrated long, slender, branching microvilli.

Conclusion: Familiarity with the cytomorphologic features and clinical presentation of WDPM, knowledge of the exact anatomic location and consideration of the appropriate differential diagnosis combined with ancillary studies are the keys to an accurate diagnosis.

In plain English

In this case report, the authors described a 64-year-old woman, treated for colon cancer 11 years earlier, who was referred to M. D. Anderson Cancer Center for a left adrenal nodule. A CT scan also showed a 4.2-cm mass that appeared to sit on the posterior surface of the liver's right lobe. The article states she had no history of asbestos exposure. Cells taken from the mass with a fine needle looked uniform, with minimal atypia, and were first interpreted as a well-differentiated papillary neoplasm of the liver. At surgery, it proved to be a peritoneal mass attached by a stalk (pedicle) to the liver. Staining tests and electron microscopy confirmed well-differentiated papillary mesothelioma (WDPM), which the authors described as usually following an indolent course. She was disease free 1.5 years after surgery. The authors concluded that familiarity with the tumor's cell features and clinical presentation, knowledge of its exact location and consideration of the appropriate differential diagnosis, combined with ancillary studies, are the keys to accurate diagnosis. They noted that follow-up was relatively short and long-term follow-up is needed.

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 64-year-old woman with a history of colonic adenocarcinoma 11 years earlier, referred to The University of Texas M. D. Anderson Cancer Center (Houston, Texas) for evaluation of a left adrenal nodule
• Exposure: No asbestos exposure: the article states that the patient had no history of asbestos exposure
• Main results:
  • CT scan of this patient showed a 4.2-cm, low-density, solitary mass on the posterior surface of the right lobe of the liver, in addition to a 3.0-cm left adrenal mass
  • The fine needle aspirate showed uniform tumor cells with minimal atypia, resembling benign mesothelial cells. The cytologic interpretation was a well-differentiated papillary neoplasm of the liver
  • At surgery, the presumed liver mass was in fact a peritoneal mass attached by a pedicle to the posterior surface of the right lobe of the liver. The resected mass measured 5.0 by 5.0 by 2.0 cm
  • Tumor cells were strongly positive for calretinin and pancytokeratin and focally positive for WT-1. They were negative for cytokeratin 5/6, Ber-EP4, MOC-31 and CD31. About 2% of tumor cells were positive for Ki-67
  • Electron microscopy showed numerous long, slender, branching microvilli on the tumor cell surfaces, described as a characteristic feature of mesothelial cells
  • The left adrenal mass, aspirated 2 weeks later, was consistent with a cortical adenoma. The patient was disease free 1.5 years after resection of the WDPM
• The authors' conclusion: The authors concluded that familiarity with the cell features and clinical presentation of WDPM, knowledge of the exact anatomic location, and consideration of the appropriate differential diagnosis, combined with ancillary studies, are the keys to an accurate diagnosis
• Limitations the authors state:
  • Follow-up of this case was relatively short. Long-term follow-up is needed to determine the natural behavior of the lesion

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: Cytology, Well-Differentiated Papillary Mesothelioma, Mesothelioma, Peritoneum, Asbestos Exposure, Colorectal Cancer, Aspirate, Cell Block.

Related studies

• Well-differentiated papillary mesothelioma of the peritoneum: a diagnostic dilemma on fine-needle aspiration cytology — J.G. Nasit, G. Dhruva (2014)
• Fine-needle aspiration of a well-differentiated papillary mesothelioma in the inguinal hernia sac: A case report and review of literature — Y.Y. Wheeler, F. Burroughs, et al. (2009)
• Malignant biphasic peritoneal mesothelioma in a child: fine-needle aspiration cytology, histopathology, and immunohistochemical features along with review of literature — S.K. Arora, R. Srinivasan, et al. (2012)
• Fine needle aspiration cytology in malignant mesothelioma of the tunica vaginalis testis — R. Gupta, P. Dey, et al. (2011)
• Pulmonary acantholytic squamous cell carcinoma with focal signet ring cell morphology mimicking malignant mesothelioma on fine needle aspiration cytology: a case report — S.E. Choi, H.S. Park (2016)
• Thoracic splenosis diagnosed by fine-needle aspiration cytology: a case report — S. Syed, P. Zaharopoulos (2001)

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