Metastatic bone lesions are cancerous cells that have traveled from other organs in the body and begun growing on the bone tissue. The cells look like cells from the organ they originated from but have grown into the tissues of the skeleton. More than 1.2 million new cancer cases occur each year, according to the American Academy of Orthopaedic Surgeons, and half of these new tumors metastasize, or spread to the bones. Understanding which types of cancer most commonly cause metastatic bone lesions aids in the diagnosis and treatment of this disease.
Breast Cancer
Breast cancer often spreads to the bone, states BreastCancer.org. The cancer begins in the bone tissue, then as it grows, cancer cells break off and travel to the skeleton. Once on the bone, these cells begin to proliferate and infiltrate the bone tissue. This can cause severe bone pain. If only a few cancer cells have affected the bone, the best treatment to relieve the pain is to remove the growing tumors. Usually, physicians use local external beam radiation therapy to target and destroy the metastatic bone lesions. This treatment provides significant reduction or complete relief of the bone pain in 85 percent of cases. Diffuse metastatic bone lesions caused by breast cancer should be treated with aggressive chemotherapy.
Prostate Cancer
Prostate cancer originates in the prostate gland in men. This cancer can spread to the bones of the pelvis and leg. Metastasis from the prostate to the bone is usually incurable, according to BoneTumor.org. There are treatments, however, that can slow and even prevent the further growth and spread of the metastatic bone lesion. Prostate cancer that spreads to the bone results in a combination of bone formation and bone breakdown. Overall, more bone is made, and the affected bone looks abnormally large and dense. However, this bone formation is not structurally intact and is weaker than normal bone. Patients may experience bone pain and frequent fractures.
Lung Cancer
Metastatic bone lesions can come from lung cancer, according to the Mayo Clinic. Lung cancer begins in the lung but often spreads to the bones, brain, liver and adrenal glands. When lung cancer spreads to the bone, it most often reaches nearby bone first. Some of the more commonly affected bones include the ribs, spine and upper arm, according to the American Academy of Orthopaedic Surgeons. Bone pain, anemia and weakened bones are the most common symptoms of bone metastasis. If the lung cancer cells spread to the spine, they can cause damage to nerves near the spine and lead to paralysis or weakness of the upper or lower limbs.
