Primary Cancerous Bone Tumors
Multiple myeloma, the most common type of primary cancerous bone tumor, originates in the bone marrow cells that produce blood cells (see Section 14, Chapter 175). This tumor may affect one or more bones, so pain may occur in one location or in several. If only one bone is involved, the condition is called plasmacytoma; if more than one bone is involved, the condition is called multiple myeloma. Treatment is complex and may include chemotherapy, radiation therapy, and surgery.
Osteosarcoma (osteogenic sarcoma) is the second most common type of primary cancerous bone tumor. Although most common in people aged 10 to 20 years, osteosarcomas can occur at any age. Older people who have Paget's disease (see Section 5, Chapter 61) sometimes develop this type of tumor. About half these tumors occur in or around the knee, but they can originate in any bone. They tend to spread (metastasize) to the lungs. Usually, these tumors cause pain and swelling. A biopsy is needed for diagnosis.
Osteosarcomas are usually treated with a combination of chemotherapy and surgery. Usually, chemotherapy is given first; pain often subsides during this phase of treatment. Then the tumor is surgically removed. About 75% of people who have this type of tumor survive for at least 5 years after diagnosis. Because surgical procedures have improved, the affected arm or leg can usually be saved; in the past, the affected limb often had to be amputated.
Fibrosarcomas and malignant fibrous histiocytomas are similar to osteosarcomas in appearance, location, symptoms, and prognosis. Treatment is the same as for osteosarcoma.
Chondrosarcomas are tumors composed of cancerous cartilage cells. Many chondrosarcomas are slow-growing or low-grade tumors, meaning that they are less likely to spread than some other tumors; they often can be cured with surgery. However, some chondrosarcomas are high-grade tumors, which tend to spread. A biopsy is needed for diagnosis. During treatment, a chondrosarcoma must be completely removed surgically, because it does not respond to chemotherapy or radiation therapy. Amputation of the arm or leg is rarely necessary. More than 75% of people who have a chondrosarcoma survive if the entire tumor is removed.
Ewing's tumor (Ewing's sarcoma) is a cancerous tumor that affects males more often than females and appears most commonly in people aged 10 to 20 years. Most of these tumors develop in the arms or legs, but they may develop in any bone. Pain and swelling are the most common symptoms. Tumors may become quite large, sometimes affecting the entire length of a bone. Although CT and MRI can help determine the exact size of the tumor, a biopsy is needed for diagnosis. Treatment consists of a combination of surgery, chemotherapy, and radiation therapy, which can cure more than 60% of people who have Ewing's tumor.
Malignant lymphoma of bone (reticulum cell sarcoma) is a cancerous tumor that usually affects people in their 40s and 50s. It can originate in any bone or elsewhere in the body and then spread to bone. Usually, this tumor causes pain and swelling, and the damaged bone is prone to fractures. Treatment usually consists of a combination of chemotherapy and radiation therapy, which appears to be as effective as surgical removal of the tumor. Amputation is rarely necessary.
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