18F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography fused imaging in malignant mesothelioma patients: looking from outside is not enough

Our plain-English summary of 18F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography fused imaging in malignant mesothelioma patients: looking from outside is not enough, by E. Roca, S. Laroumagne, T. Vandemoortele, et al (Lung Cancer, 2013).

The study

• Authors: E. Roca, S. Laroumagne, T. Vandemoortele, S. Berdah, H. Dutau, F. Maldonado, P. Astoul
• Journal: Lung Cancer
• Published: 2013;79(2):187-90
• Type of article: Case report
• Cited by: 17 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Malignant mesothelioma (MM) is an uncommon neoplasm with a poor prognosis usually associated with asbestos exposure. 18F-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) has become an invaluable tool for the diagnosis, staging, and prognosis of this severe disease as it combines both anatomic and functional information in a single imaging procedure, allowing for improved management of this disease. For many authors, 18F-FDG-PET/CT is the cornerstone of the pre-therapeutic evaluation of mesothelioma patients, particularly when multimodal therapy (including extra-pleural pneumonectomy or omentectomy) is considered. However, while characteristic patterns have been reported as predictive of macroscopic pleural or peritoneal involvement, false negative findings are possible, both for pleural and peritoneal mesothelioma, during the initial diagnosis or during the patient's surveillance as illustrated by this report of three cases of suspected MM with negative PET/CT. This report highlights the limitations of PET/CT in the diagnostic evaluation of MM and the importance of histopathological confirmation by thoracoscopy and/or laparoscopy, which remain the most important diagnostic procedures in MM.

Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

In plain English

This case report described three patients with malignant mesothelioma whose FDG PET/CT scans, which combine PET and CT imaging, gave false-negative results at the site being evaluated. In each case, the diagnosis was confirmed by direct viewing and biopsy during thoracoscopy or laparoscopy within 2 weeks of the scan. The first patient was a 78-year-old man who had worked as a shipyard welder for 30 years. His scan showed only minimal uptake, but thoracoscopy found diffuse pleural carcinomatosis, and biopsies showed epithelial mesothelioma. The second, a 63-year-old man with a significant smoking history and asbestos exposure, also had a negative scan, and pleural biopsies confirmed epithelial mesothelioma. The third, a 71-year-old man diagnosed in 2005 with epithelial malignant pleural mesothelioma, developed ascites seventy-two months after completing multimodal therapy. His scan showed uptake in the chest but was negative in the peritoneum, yet laparoscopy found diffuse peritoneal carcinomatosis consistent with epithelial mesothelioma. The authors concluded that thoracoscopy and laparoscopy remain the most important diagnostic procedures in mesothelioma. Because no molecular biology analysis of the pleural samples was done, the authors said they could not explain the difference between the scans and the endoscopic findings in biological terms.

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 (three cases)
• Who was studied: Three men aged 78, 63 and 71 with suspected malignant mesothelioma. The authors are based at a thoracic oncology department of Hôpital Nord, Marseille, France. The third patient was diagnosed in 2005 and remained in complete clinical remission until January 2012.
• Exposure: Case 1 had occupational asbestos exposure as a shipyard welder for 30 years and was a never-smoker. Case 2 had asbestos exposure and a significant smoking history. No exposure is described for Case 3. No fiber type is given.
• Main results:
  • Case 1: the pleural effusion showed minimal FDG uptake (maximum SUV 1.9 g/ml; hepatic SUV 2.2 g/ml), and the scan was judged negative for malignancy. Thoracoscopy then showed diffuse pleural carcinomatosis.
  • Case 1: pleural biopsies confirmed epithelial malignant mesothelioma.
  • Case 2: the FDG PET/CT was negative, but medical thoracoscopy found nodules on the costal and diaphragmatic pleura, and biopsies confirmed epithelial malignant mesothelioma.
  • Case 3: seventy-two months after completing multimodal therapy for epithelial malignant pleural mesothelioma, the patient developed ascites. Paracentesis was negative for malignant cells. The PET/CT showed increased uptake in the chest (pleural nodules and mediastinal lymph nodes) but was negative at the peritoneum.
  • Case 3: laparoscopy showed diffuse peritoneal carcinomatosis, and the nodules were consistent with epithelial mesothelioma.
• The authors' conclusion: The authors concluded that thoracoscopy and laparoscopy remain the most important diagnostic procedures in malignant mesothelioma, to obtain tissue and confirm the diagnosis. They highlighted the importance of thoracoscopy in asbestos-exposed patients presenting with a pleural effusion.
• Limitations the authors state:
  • No molecular biology analysis of the pleural samples was performed, so the authors could not explain the difference between PET/CT and endoscopic findings in terms of biological parameters.

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: Malignant Mesothelioma, Neoplasm, Prognosis, Asbestos Exposure, Staging, Mesothelioma, Multimodal Therapy, Pneumonectomy.

Related studies

• Clinical implications of 18F-fluorodeoxyglucose positron emission tomography/computed tomography at delayed phase for diagnosis and prognosis of malignant pleural mesothelioma — Y. Abe, K. Tamura, et al. (2012)
• Positron Emission Tomography/Computed Tomography for the Pleural Staging of Malignant Pleural Mesothelioma: How Accurate Is It? — V. Pinelli, E. Roca, et al. (2015)
• High performance of F-fluorodeoxyglucose positron emission tomography and contrast-enhanced CT in a rapid outpatient diagnostic program for patients with suspected lung cancer — P. Brocken, H.F. van der Heijden, et al. (2014)
• Use of computed tomography and positron emission tomography/computed tomography for staging of local extent in patients with malignant pleural mesothelioma — T. Frauenfelder, P. Kestenholz, et al. (2015)
• Integrated positron emission tomography-computed tomography does not accurately stage intrathoracic disease of patients undergoing trimodality therapy for malignant pleural mesothelioma — J. Pilling, J.A. Dartnell, et al. (2010)
• The role of fluorodeoxyglucose-positron emission tomography/computed tomography in differentiating between benign and malignant adrenal lesions — P. Ozcan Kara, T. Kara, et al. (2011)

Browse more research in Lung Cancer, or return to medical research.