Abstract
Multiple myeloma represents a neoplastic proliferation of plasma cells, and is often diagnosed as solitary plasmacytoma of bone before multiple lesions form. The lesions frequently occur in the 4th to 7th decades of life, but may occur in younger patients. Multiple myeloma is usually found in the molar, angle, ramus and condyle regions of the mandible. Radiographical features of the lesion indicate a predominantly osteolytic lesion with various characteristics that are useful in differential diagnosis. Multiple punched-out lesions are a typical in the skull.
We encountered a patient displaying a radiolucent lesion in the right molar region of the mandible on first examination. The patient was initially diagnosed with malignant lymphoma in the oral surgery department of another general hospital. Enhanced computed tomography indicated a heterogeneous expanded mass that showed irregular destruction of the mandible. Magnetic resonance imaging demonstrated signal hypointensity on axial T1-weighted imaging (T1WI), and signal hyperintensity compared with fatty bone marrow on T2-weighted imaging with fat saturation. Gadolinium-enhanced T1WI demonstrated a light homogeneous enhanced mass. Scintigraphy of the whole body revealed hot lesions in the right humerus and femur.
The final diagnosis was multiple myeloma based on data from radiographic diagnostic imaging, immunohistochemistry, clinical laboratory examination and FACS analysis of tumor cells.
