Bone cancer is a malignancy that originates and develops in bone tissue. Less than one percent of all cancer diagnosis are bone cancers, as they are rare in the general population. The most common bones in the body affected by bone cancer are the long bones in the legs and arms as well as the pelvis. The three primary forms of bone cancer include chondrosarcoma, osteosarcoma, and Ewing sarcoma. Symptoms indicative of bone cancer include swelling and redness around the affected bone, fatigue, bone pain, bone fracture, and unexplained weight loss. A bone cancer diagnosis is made using physical examination, magnetic resonance imaging, positron emission tomography, bone scans, computerized tomography, x-rays, and tissue biopsy. Depending on the location and stage of bone cancer, surgery, chemotherapy, or radiation therapy may be used to treat it.
Paget's Disease Of The Bone
An individual's risk of developing bone cancer can be a late complication that occurs due to pre-existing Paget's disease of the bone. Paget's disease of the bone is a disease that impairs an individual's natural bone recycling process. Over time, the body breaks down old bone tissues and replaces it with new bone tissue to help maintain healthy bone density. Paget's disease of the bone affects bones in the pelvis, spine, skull, and legs. An individual's risk of developing Paget's disease of the bone increases as they reach their sixth decade of life. Paget's disease of the bone can cause the body to produce new bone at a faster rate than it would otherwise. The new bone generated in this process is weaker and not as hard as healthy bone tissue. The altered characteristics and invasiveness of the excessive new bone growth can cause pain due to bones that have become deformed. Since cancer is caused by gene mutations that occur in the cells, an individual affected by Paget's disease of the bone is at an increased risk of developing bone cancer. The constant remodeling process the bone is undergoing provides greater opportunity for a cancer-causing mutation to occur.
An individual who has undergone radiation therapy for the treatment of a previous disease has a greater risk of developing bone cancer. Prior radiation therapy is a relatively rare cause of bone cancer, but it does happen. Typically, bone cancers that develop due to previous radiation therapy will manifest between one and two decades following the last radiation treatment. For previous radiation therapy to cause carcinogenesis in bone, it must have been administered to the area in question in very high doses. The high doses of radiation cause damage to the bone tissue that takes many years for the patient's body to fully repair. During the repair and regeneration process that occurs when parts of the bone have become damaged, the tissue undergoes multiple changes. The cellular DNA damage caused by the radiation treatment itself is compounded with the changes that follow it to increase the patient's risk of developing cancer in the affected area of the bone. The mechanisms involved in bone remodeling and repair processes provide a window of opportunity for a cancer-causing mutation to occur in the cellular DNA.
Osteochondroma And Chondroma
Individuals affected by either osteochondroma or chondroma are at an increased risk of developing cancer in their bone tissue. Multiple osteochondromas syndrome is a hereditary condition that produces numerous bumps on a patient's bone. These growths are formed out of abnormal cartilage and can cause the patient to experience fractures and deformities in their bones. This syndrome occurs as a result of a mutation in the EXT1, EXT3, or EXT2 gene. Multiple osteochondromas syndrome puts a patient at an increased risk of developing a form of bone cancer called chondrosarcoma. Chondroma describes a noncancerous tumor on the bone that develops from cartilaginous material. Chondromas occur most commonly on the small bones of an individual's feet and hands, but can also develop in their ribs, humerus, and femur. An individual affected by one or more chondromas is at an increased risk of developing bone cancer because there is more growth that provides a better opportunity for a cancer-causing mutation to occur.
Exposure To Radium Or Plutonium
An individual who has experienced occupational exposure to radium or plutonium for some time is at a higher risk of developing bone cancer than the rest of the population. When an individual is exposed to compounds such as radium or plutonium, it uses their lungs as a gateway into their circulatory system. Once in circulation, radium or plutonium is rapidly distributed throughout the body tissues. These compounds begin to deplete from the soft tissues first, making their way into an individual's stool for excretion. The concentration of radium and plutonium is then shifted into the hard tissues or bones. An affected individual's bones become the primary storage module for these compounds, much similar to the way calcium is stored in the bones. Upon long term exposure to high levels of radium or plutonium, the buildup of these compounds in the bone tissue causes the bone and its vessels to become damaged. This damage increases the likelihood a cancer-causing mutation occurs in the portion of the cellular DNA responsible for cell multiplication, growth, and apoptosis.
A Li-Fraumeni syndrome patient is at a greater risk of developing cancer in their bone tissues than an individual who is not affected by the syndrome. Li-Fraumeni syndrome is a hereditary disorder characterized by a mutation in an individual's TP53 tumor suppressor gene. This mutation causes the body to have an impaired ability to prevent malignancy from forming in the tissues throughout the body. However, bone cancer is only one of the common types of cancer known to develop in individuals affected by Li-Fraumeni syndrome. Aside from osteosarcoma, soft tissue sarcoma, breast cancer, acute leukemia, adrenocortical carcinoma, brain cancer, and central nervous system tumors are also known to occur. There are no symptoms that occur in Li-Fraumeni syndrome patients aside from the development of cancer. Patients diagnosed with this syndrome are advised to take precautions to ensure early detection in case osteosarcoma or another form of cancer develops in their body.