Presentation
Lower back and pelvic pain. History of falling down a year ago.
Patient Data
A T2-hyperintense intraosseous lesion in the right sacral ala without extension to the sacroiliac joint and the sacral neural foramina
No associated extraosseous soft tissue mass
Marked decreased the height of L1 vertebrae with no evidence of marrow edema due to old vertebral compression fracture
Disc bulging at L4-L5, L5-S1 levels
Multilevel vertebral hemangiomas.
Biopsy proven case of plasma cell dyscrasia positive for CD138 and negative for CD20.
Case Discussion
Subsequent nuclear medicine (not shown) displayed hypermetabolic bone lesion involving the right sacral ala with heterogeneous abnormal increased FDG uptake. No definite evidence of other medullary or extramedullary abnormal hypermetabolic lesions.
A solitary plasmacytoma is a neoplastic monoclonal plasma cell disorder in either bone or soft tissue. The thoracic vertebrae are the most common location of infiltration followed by lumbar, sacral, and cervical vertebrae. The main differential diagnosis for solitary plasmacytoma is a solitary metastasis or lymphoma which is difficult to delineate from each other on imaging.