CT and MRI Findings of Solitary Extramedullary Plasmacytoma: A Series of Ten Case Reports and Review of Literature

Objective The study aimed to analyze computed tomography and magnetic resonance imaging features of patients with solitary extramedullary plasmacytoma. Methods Ten cases with solitary extramedullary plasmacytoma were included in this study. CT and MRI features of solitary extramedullary plasmacytoma were retrospectively analyzed. Results This study included both males (n = 8) and females (n = 2), with a median age of 48 (range 21-72 years old). The organs or anatomical structures involved were nasopharynx (n = 3), orbit (n = 1), left tentorium (n = 1), nasal cavity and meatus (n = 2), small intestine and mesentery (n = 1), as well as posterior thoracic wall (n = 2). The median maximum diameter of the tumors was 3.2 cm (range 0.8-15.2 cm). The tumor shapes were round (n = 7), stripped (n = 1), irregular (n = 1), and nodular (n = 1). The margin of the tumors was well-defined (n = 7) and partially well-defined (n = 3). There were 3 cases with bone destruction and 1 with a tissue invasion adjacent to the tumor, calcification (n = 1), and cystic degeneration (n = 2). Enlarged tumoral vessels (n = 4) could also be observed. The CT attenuation and MR signal intensity of tumors were heterogeneous (n = 4) and homogenous (n = 6). After the injection of the contrast agent, marked (n = 5), mild (n = 1), mild to moderate (n = 1), and delayed enhancement (n = 1) could be observed. Conclusion A well-defined homogeneous solitary mass occurring at the head and neck with a marked enhancement, an adjacent tissue invasion, enlarged tumoral vessels, and bone destruction can indicate the diagnosis of solitary extramedullary plasmacytoma.