Solitary plasmacytoma of maxillofacial bones: correlation of CT features with pathological findings

Abstract

Objective: To explore the CT features of solitary plasmacytoma (SP) of maxillofacial bones and correlation with pathological findings. Methods and materials: We retrospectively reviewed the clinical, CT and pathological features of SP in the maxillofacial bones. 16 patients with clinically and histologically proven SP of maxillofacial bones were involved. They were aged from 27 to 79 years old (median 55.5 years old), and included 12 males and 4 females (males vs females: 3:1). All patients performed CT examination, in whom 13 patients underwent enhanced scanning and 3 plain scanning. The CT images were assessed for lesion location, size (maximum diameter), shape (round, oval and irregular), boundary (defined and illdefined), bone changes (bone destruction, residual bone, sclerotic margin and periosteal reaction), density of soft tissue mass and enhancement manifestations, and invasion of adjacent structures. Results: 13 patients suffered from SP in the mandible, 2 in the zygoma, and 1 in the maxilla and hard palate. The maximum diameter of lesions ranged from 2.4 to 8.2 cm (mean 3.93 ± 1.435 cm). Most lesions were founded as a solitary osteolytic lesions (15/16, 93.75%) with round or ovoid shape (13/16, 81.25%), smooth margin (16/16, 100%) and defined boundary (16/16, 100%) in bone marrow. They destroyed bone cortex (15/16, 93.75%) and had residual bone (10/16, 62.5%), without sclerosis margin (15/16, 93.75%) and periosteal reaction (14/16, 87.5%). They easily formed soft tissue masses (16/16, 100%) and invade adjacent anatomical structures (15/16, 93.75%). The density of lesions was usually uniform (12/16, 75%) with strong enhancement. There was a significant difference in CT values between plain and enhanced scanning [50.75 ± 9.140 Hounfield unit (HU) vs 101.0 ± 28.830 HU; p < 0.001), with the mean difference of CT values 50.25 HU. Conclusions: SP is predominant in the mandible of elderly male patients. A solitary, round or ovoid, well-defined, osteolytic, invasive mass in bone marrow, which destroys bone cortex, has residual bone, no sclerosis margin and periosteal reaction, and shows strong enhancement, is suggestive of this diagnosis.