Synonyms

• Solitary plasmacytoma of Bone
• extramedullary plasmacytoma

Category

Bone

Behaviour

Malignant

Grade

High

Gender

Male

Tissue of Origin

Other

Epidemiology

• Solitary clonal plasma cell malignancy
• Often precursor to multiple myeloma
• 70% progress to MM within 5 years

Clinical Features

• Bone pain
• Local mass effect if large

Location

• Spine most common
• Pelvis
• Ribs

Imaging

• MRI or CT: lytic/sclerotic lesion
• PET-CT: assess for other lesions

Pathology

• Monoclonal plasma cell proliferation
• CD38+, CD138+
• Monoclonal immunoglobulin production

Genetics

Recurrent translocations like MM

Treatment

• Chemotherapy and radiotherapy
• Close surveillance for progression to MM

Prognosis

• Variable - many progress to MM
• Isolated lesion better prognosis if treated definitively

Key Points

• Solitary lesion but High risk of progression
• Treat as High-risk disease
• Close monitoring essential

Workup - Blood Tests

• FBC, U&E, LFTs, monoclonal protein
• Free light chains, beta-2 microglobulin

Workup - Local Imaging

• MRI Bone marrow and solitary lesion
• Whole-body imaging to rule out multiple lesions

Workup - Biopsy

• Confirm monoclonal plasma cell proliferation
• Cytogenetics for risk stratification

Workup - Staging

• Confirm solitary lesion with imaging
• FISH for prognostic markers

Workup - Other

• Haemato-oncology MDT
• Close surveillance for progression