J Korean Soc Radiol.  2017 Jun;76(6):429-433. 10.3348/jksr.2017.76.6.429.

Pleural Localized Malignant Mesothelioma Mimicking a Benign Solitary Fibrous Tumor of the Pleura on Chest Computed Tomography: A Case Report

• Park HR
• Chong S
• Kim MK

• KMID: 2379326
• DOI: http://doi.org/10.3348/jksr.2017.76.6.429

Abstract

Pleural malignant mesotheliomas arise from mesothelial cells in the pleura. They are characterized as diffuse or localized malignant mesotheliomas (LMM). Diffuse malignant mesotheliomas spread diffusely along pleural surfaces, while LMM are well-circumscribed nodular lesions with no gross or microscopic diffuse pleural spreading. Therefore, LMM can be radiologically confused with solitary fibrous tumors of the pleura (SFTP), which commonly presents as a solitary, well-demarcated peripheral mass abutting the pleural surface upon the completion of a computed tomography (CT). Therefore, this study reports on a 63-year-old female patient with a pathologically-proven LMM of the pleura, mimicking a benign SFTP upon having a chest CT. Although LMM is extremely rare, FDG PET/CT should be recommended for adequate tumor management in order to avoid misdiagnosing the tumor as a benign SFTP when an interfissural or pleural-based mass is seen on the chest CT.

MeSH Terms

Female
Humans
Mesothelioma*
Middle Aged
Pleura
Positron-Emission Tomography and Computed Tomography
Solitary Fibrous Tumor, Pleural*
Solitary Fibrous Tumors*
Tomography, X-Ray Computed

Figure

• 

  Fig. 1 A 63-year-old woman with localized malignant mesothelioma. A. The chest radiograph shows a 4 cm ovoid mass in the right paraspinal area inferior to the posterior junctional line (arrows). B, C. Mediastinal (B) and lung (C) window images of contrast enhanced chest CT scan reveal a well-defined ovoid 3.8 cm pleural based mass (arrows) in a mediastinal reflection in the posterior aspect of the tracheal carina. The mass shows a mild homogeneous enhancement (arrow in B) and an interfissural location (arrow in C). D. FDG PET/CT scan shows a positive FDG uptake of the mass with 8.5 of the maximum standardized uptake value (SUVmax) (arrow). E. Photograph of the surgical specimen grossly reveals a well demarcated solid grayish mass. F. Photomicrograph of the surgical specimen shows atypical mesothelial cell proliferation with papillary and solid pattern. Cell groupings and cytologic atypism are also present, which is suggestive of malignancy (hematoxylin & eosin, × 100). G. Photomicrographs of the surgical specimen show a strong positive reaction for calretinin, consistent with mesothelial origin (immunohistochemical stain, × 200).

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