Bone marrow is a spongy network of tissue that fills the center of most bones. Cancerous plasma cells, or myeloma, in the bone marrow can form plasma cell tumors that spread to the bone's outer covering.

Eventually, the myeloma cells wear away portions of bone, leaving small holes called osteolytic lesions. This wearing-away process is called resorption, and it leaves bones weak and fragile.

Common Early Symptoms of Myeloma Bone Lesions

• Bone pain
• Fractures
• Spinal cord compression

High blood calcium levels (hypercalcemia), excessive calcium released from diseased bone, may reduce one's appetite, may cause nausea, thirst, constipation, tiredness, confusion, and (if untreated) coma.

Read more about bone health support resources.

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