Plasmacytomas (Bsh 2004)
Epidemiology & Clinical Features
Male:Female 2:1, median age 55
Occur in spine twice as often as other sites
Presents as pain or cord/nerve root compression
Base of skull lesions can cause cranial nerve palsies
Solitary Bone Plasmacytoma (SBP)
Majority with apparent SBP develop myeloma after 2-4 years
i.e. undetected myeloma at diagnosis (MRI spine may increase pick-up rate)
Increased likelihood of progression to myeloma with:
Low uninvolved Ig, Axial disease, Older age, Size >5cm, monoclonal band post-Rx
Diagnostic criteria
Single area of bone destruction due to clonal plasma cells + normal BM biopsy + normal skeletal survey + no myeloma ROTI + absent or low monoclonal Ig
Treatment
Radical radiotherapy of approx. 40 Gy with a 2cm margin
Post-treatment regular review and monitoring for myeloma development
Solitary Extramedullary Plasmacytoma (SEP)
Less common than SBP but better prognosis
90% occur in head and neck but can be anywhere in body
Diagnostic criteria
Single extramedullary mass of clonal plasma cells + normal BM biopsy + normal skeletal survey + no myeloma ROTI + absent or low monoclonal Ig
Due to soft tissue mass and rarity, can be confused with Non-hodgkin lymphomas
Treatment
High cure rates with radiotherapy of approx. 40 Gy with 2cm margin
Surgery may be considered if not ‘mutilating’