Korean J Radiol.  2013 Aug;14(4):673-676. 10.3348/kjr.2013.14.4.673.

Inflammatory Pseudotumor in the Mediastinum: Imaging with 18F-Fluorodeoxyglucose PET/CT

• Yoon SH
• Lee S
• Jo KS
• Lee DH
• An YS
• Yoon JK
• Lee SJ

• KMID: 1715773
• DOI: http://doi.org/10.3348/kjr.2013.14.4.673

Abstract

Mediastinal inflammatory pseudotumor is a rare benign disease with its capability for local invasion and rapid growth. We present a case of middle-mediastinal inflammatory pseudotumor and report its contrast-enhanced chest computed tomography, 18F-fluorodeoxyglucose positron emission tomography/computed tomography and pathologic findings.

Keyword

Mediastinal neoplasm; Inflammatory pseudotumor; 18F-fluorodeoxyglucose PET/CT

MeSH Terms

Adult
Diagnosis, Differential
Fluorodeoxyglucose F18/*diagnostic use
Granuloma, Plasma Cell/*diagnosis
Humans
Male
Mediastinal Diseases/*diagnosis
Positron-Emission Tomography/*methods
Radiopharmaceuticals/*diagnostic use
Tomography, X-Ray Computed/*methods
Fluorodeoxyglucose F18
Radiopharmaceuticals

Figure

• 

  Fig. 1 Imaging and histopathologic findings of mediastinal inflammatory pseudotumor. A. Chest X-ray showed large mass in right upper mediastinum. B. Contrast-enhanced chest CT demonstrated bulky mass in right paratracheal space with mild homogeneous enhancement. C, D. 18F-FDG PET/CT (C. maximum intensity projection, D. fusion transaxial image) showed heterogeneous FDG accumulation in huge right paratracheal mass (SUVmax = 5.0). SUVmax = maximum standardized uptake value, 18F-FDG = 18F-fluorodeoxyglucose. On histopathologic examination, tumor was composed of lymphoid cells, plasma cells, histiocytes and fibroblastic cells in fibrocollagenous stroma (E. hematoxylin-eosin stain, × 400). Immunohistochemical analysis revealed that CD163 was positive to histiocytes but negative to fibroblastic spindle cells (F. × 400).

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