What is the definition of multiple myeloma (MM) bone disease?

From the Guidelines

Multiple myeloma bone disease is defined as the skeletal complications that occur in patients with multiple myeloma, characterized by bone destruction, pain, fractures, and hypercalcemia, and is typically diagnosed by the presence of lytic lesions, osteoporosis, or fractures in 79% of patients at the time of diagnosis, as noted in the study by 1.

Key Characteristics of Multiple Myeloma Bone Disease

• Bone destruction and pain are common symptoms
• Fractures and hypercalcemia are frequent complications
• Lytic lesions, osteoporosis, and pathological fractures are characteristic radiographic findings
• The vertebrae, skull, sternum, ribs, pelvis, and proximal humeri and femora are the most frequent sites of involvement, as reported in the study by 1

Diagnosis and Treatment

• Diagnosis is typically made by conventional roentgenograms or advanced imaging techniques such as magnetic resonance imaging or positron emission tomography computed tomography scanning, as mentioned in the study by 1
• Treatment involves addressing the underlying myeloma with chemotherapy and targeted therapies, as well as bone-specific treatments like bisphosphonates, radiation therapy, and surgical intervention, as recommended in the study by 1

Importance of Early Treatment

• Early treatment is crucial to prevent skeletal-related events and improve progression-free survival, as demonstrated in the MRC IX Trial cited in the study by 1
• Bisphosphonate therapy, such as zoledronic acid, is recommended for all patients with active multiple myeloma, regardless of the presence of lytic bone disease, as stated in the study by 1

From the Research

Definition of Multiple Myeloma Bone Disease

Multiple myeloma bone disease is characterized by:

• Lytic lesions or osteopenia 2, 3, 4, 5, 6
• Severe pain, pathological fracture, spinal cord compression, vertebral collapse, and hypercalcemia 2, 3, 4, 5, 6
• Asynchronous bone turnover with increased osteoclastic bone resorption and decreased bone formation 4, 5

Pathophysiology

The pathophysiology of multiple myeloma bone disease involves:

• Increased osteoclast proliferation and activity 2, 3, 4, 5, 6
• Inhibition of bone-forming osteoblasts 2, 3, 4, 5, 6
• Imbalance between bone regeneration and bone resorption 2
• Cytokine deregulation within the bone marrow milieu 6

Clinical Features

Clinical features of multiple myeloma bone disease include:

• Skeletal-related events (SRE) such as severe bone pain, pathological fractures, vertebral collapse, hypercalcemia, and spinal cord compression 6
• Negative impact on quality of life and overall survival 6
• Diffuse osteopenia, focal lytic lesions, pathologic fractures, hypercalcemia, and bony pain 4, 5