Myeloma

Modern Study Review (AI-Generated)

High-Yield Summary

Multiple myeloma is a malignant plasma cell neoplasm characterized by clonal proliferation within the bone marrow, leading to osteolytic bone destruction and systemic manifestations. It predominantly affects males in their 60s and presents with bone pain, anemia, hypercalcemia, and renal dysfunction. Early diagnosis and risk-adapted therapy are critical to improving survival and preserving function. Orthopaedic management focuses on stabilizing pathologic fractures and preventing skeletal-related events.

Key Diagnostic Findings

Anatomy

• Originates from malignant plasma cells in the bone marrow.
• Commonly affects axial skeleton: vertebrae, ribs, pelvis, and proximal long bones.

Clinical Presentation

• Bone pain (vertebrae, ribs, pelvis).
• Symptoms of anemia (fatigue, pallor).
• Hypercalcemia symptoms (confusion, constipation).
• Possible pathologic fractures or spinal cord compression.

Imaging

Laboratory

• Anemia, elevated serum calcium.
• Bone marrow plasmacytosis >30%.
• Serum protein electrophoresis: monoclonal (M) protein spike.
• Immunofixation: monoclonal immunoglobulins (IgG, IgA most common).
• Urine: Bence Jones proteinuria (monoclonal light chains).

Classification Systems

• Revised International Staging System (R-ISS): Incorporates serum ?2-microglobulin, albumin, LDH, and cytogenetics for prognosis.
• Durie-Salmon Staging: Older system based on hemoglobin, calcium, M protein, and radiographic bone lesions (less used today).

Current Gold Standard Treatment

Non-operative

• Systemic chemotherapy: proteasome inhibitors (bortezomib), immunomodulatory drugs (lenalidomide), corticosteroids.
• Autologous stem cell transplant for eligible patients.
• Radiation therapy: for solitary plasmacytomas or palliation of painful bone lesions.
• Supportive care: bisphosphonates or denosumab to reduce skeletal-related events, pain control, and management of hypercalcemia.

Operative

• Indications: pathologic fractures or impending fractures with structural instability, spinal cord compression requiring decompression and stabilization.
• Procedures: internal fixation (intramedullary nails, plates), vertebroplasty/kyphoplasty for vertebral fractures.
• Goal: restore mechanical stability and preserve neurological function.

Modern Complications & Outcomes

Complications

Outcomes

• Median survival has improved significantly with novel agents and transplant.
• Functional outcomes depend on early diagnosis and timely orthopaedic intervention.
• Skeletal-related events correlate with decreased quality of life and survival.
• Multidisciplinary care is essential for optimizing pain control and function.

Classic Clinical Notes

Myeloma

• Malignant plasma cell tumor originating from marrow that usually presents with multiple bony lesions.
• Males > females; presents in 6th decade with pain usually involving vertebrae, ribs, or pelvis.

Labs:

• Anemia, elevated serum Ca, plasmocytosis in bone marrow (>30%).
• Serum electrophoresis – globulin spike.
• Immunoelectrophoresis – high levels of monoclonal immunoglobulins (M components) in serum.
• Monoclonal light chains in urine (Bence Jones proteinuria).

X-rays:

• Multiple or single small, well-circumscribed ‘punched-out’ lytic lesions.
• Little or no reaction by surrounding bone but endosteal scalloping & medullary expansion.
• With long bone involvement, may be cortical destruction with soft tissue mass.

Histology:

• Tightly packed plasma cells with eccentrically located nucleus, abundant pink cytoplasm & pale-stained juxtanuclear halo.
• Nodular foci or broad areas of amyloid deposits with no background stroma.
• Intracytoplasmic inclusions (Russell bodies).

Treatment:

• Chemotherapy & radiation (for solitary lesions).
• Internal fixation for pathologic or impending pathologic fractures.

Last Updated on January 25, 2026 by orthonet