WebMD describes lytic lesions as weak areas of the bone. Also called osteolytic lesions, these lesions occur when multiple myeloma afflicts the body. Registered nurse Karen Raymaakers also notes that myeloma cells release chemicals that lead to bone breakdown. Dr. Sheeba Thomas at Everyday Health further explains that lytic lesions occur with other forms of cancer, including breast cancer, lung cancer and kidney cancer.
Raymaakers explains that lytic lesions have a "punched-out” appearance that may occur in any bone in the body but mostly manifest in the spine, skull, pelvis and ribs. WebMD describes the cause of lytic lesions by explaining the damage from excessive plasma cells releasing unhealthy levels of protein into the blood and bones. The accumulation of the excess protein in the body causes organ damage, which grows worse when plasma cells begin to spill out of the bone marrow and deposit elsewhere in the body. Furthermore, the plasma cells crowd out normal blood cells in the bone and release chemicals that cause the body to dissolve areas of the bone. Thomas states that lytic lesions occur with other medical conditions besides multiple myeloma, including infections of the bone and even in some benign conditions. She suggests having a biopsy of one of the lesions to get a proper diagnosis.