PMC4659956_01
Extraoral (a) and intraoral (b) photographs show diffuse swelling in the right cheek and maxillary alveolar region (arrows).
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A 33-year-old Japanese man presented with diffuse swelling in the right cheek and maxillary alveolar region with mobility of the adjacent teeth, the first premolar and first and second molars (Figure 1).
Panoramic radiography shows an osteolytic lesion in the right posterior maxilla with resorption of the floor of the maxillary sinus (arrows).
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A panoramic radiograph showed an ill-defined osteolytic lesion in the right posterior maxilla with resorption of the floor of the maxillary sinus (Figure 2).
An axial CT image shows a soft tissue density mass eroding the anterior and lateral walls of right maxillary sinus (arrows).
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An axial section computed tomography (CT) image showed a soft tissue density mass measuring 45 x 35 mm in the right maxilla eroding the anterior and lateral walls of the maxillary sinus and extending into the buccal space (Figure 3).
An MRI scan shows a mass with low T1- (a) and moderate T2-weighted (b) signal intensity.
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Magnetic resonance imaging (MRI) also showed a mass with low T1- and moderate T2-weighted (Figure 4) signal intensity in the right maxilla.
An incisional biopsy specimen from the maxillary lesion (a). Hematoxylin and eosin staining of the specimen shows solid proliferation of plasmacytoid cells with eccentric nuclei and basophilic cytoplasm and partially shows atypia ((b), original magnification x40). The immunohistochemical results are positive for CD138 ((c), original magnification x40). Serum immunofixation electrophoresis shows M-protein (IgG kappa and lambda types, (d)).
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After the radiographic evaluations, an incisional biopsy of the maxillary mass was performed; histopathologic examination of the specimen showed atypical plasma cells with large hyperchromatic nuclei, binucleation, and large cytoplasms (Figures 5(a) and 5(b)). Immunohistochemically, the cells were positive for CD138 (Figure 5(c)). Serum immunofixation electrophoresis showed M-protein (IgG kappa and lambda types, Figure 5(d)).
Strong SUVs are found in the right maxillary sinus ((a), arrows), right submandibular region ((b), arrows), and left pubic bone ((c), arrows) on an 18F-FDG PET/CT scan.
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An 18F-fluorodeoxyglucose positron emission CT (18F-FDG PET/CT) image showed a strong standardized uptake value (SUV) in the right maxillary sinus, right submandibular region, and left pubic bone (Figure 6).