Multiple Myeloma with Extraosseous Involvement: Imaging Findings

Abstract

A 50-year-old female patient presented with complaints of backache, occasional on-and-off fever, and wheezing for six months. There was no history of weight loss or other significant complaints. Clinical examination showed tenderness at the mid-dorsal vertebral level. Blood investigations revealed anaemia (Hb: 10 g%), a reversal of the A/G ratio with low albumin levels (3.4 g/dL), and high globulin levels (6.7 g/dL), along with a rise in Lactate dehydrogenase (368 U/L). Alkaline phosphatase was within normal limits at 51 IU/L, and the rest of the investigations were normal. To evaluate the cause of wheezing and pyrexia, a Computed Tomography (CT) chest was performed, which demonstrated infective changes in the left lung field [Table/Fig-1a] and an ill-defined left paravertebral and epidural soft tissue mass at the D5-D6 level with a lytic lesion of the D5 vertebra [Table/Fig-1b] causing mass effect on the cord. Magnetic Resonance Imaging (MRI) of the dorsal spine was conducted for the complaints of backache, which revealed a relatively well-defined lobulated T2 hypointense and STIR (Short Tau Inversion Recovery) hyperintense lesion in the left paravertebral region with involvement of the left pedicle of the D5 vertebral body [Table/Fig-1c,d]. Based on the blood and radiological work-up, multiple myeloma and metastasis were considered as differential diagnosis. The patient then underwent a bone marrow biopsy, which revealed more than 80% plasmablasts. A dedicated comprehensive myeloma panel was conducted, showing positive Ig G and kappa bands, thus confirming the diagnosis. Urine analysis for Bence-Jones proteins also turned out to be positive. All the investigations were consistent with multiple myeloma. The patient was started on injections of bortezomib, thalidomide, dexamethasone, allopurinol, and analgesics in appropriate doses.

Keywords

• backache
• plasmablasts
• vertebra