Solitary bone plasmacytoma of spine with involvement of intervertebral disk: a case report and literature review

Primary malignant bone tumors of the spine are exceedingly rare, with solitary bone plasmacytoma (SBP) representing approximately 30% of all cases. Radiological assessments are crucial for localizing SBP and for ruling out a diagnosis of multiple myeloma (MM). Imaging features resembling a "mini-brain" appear to be distinctive for SBP. Vertebral lesions accompanied by adjacent disc space involvement typically suggest spinal infections, while the potential for SBP involvement is often overlooked. We present a case of a 61-year-old female with SBP who exhibited thoraco-lumbar spine destruction and adjacent disc space involvement. The patient sought treatment at our medical center due to lumbodorsal pain radiating bilaterally to the inguinal regions. Radiological findings revealed an osteolytic lesion involving the intervertebral disc, making it challenging to distinguish between tumor and inflammation. A biopsy of the vertebral lesion confirmed the diagnosis of SBP, which was further supported by laboratory results. Post-diagnosis, the patient underwent radiotherapy, receiving a total dose of 4000 Gy, which alleviated her symptoms. We also provide a comprehensive literature review on SBP with disc involvement to aid both clinical and radiological diagnoses.