Bone cancer is a malignant tumor that originates from bone cells. It can form in every bone of the body but in majority of cases long bones of the upper and lower extremities are affected the most. There are several types of bone cancer. It is essential to differentiate primary from secondary bone cancers. Namely, primary bone cancers develop from the bone tissue. They are more common in children although some types of bone cancer predominantly affect adults. On the other hand, secondary bone cancers do not represent tumors made of bone cells. On the contrary, they represent metastases of cancers that originate form other organs in the bone that develop after the spread of the primary tumor to the bone.
Types of Bone Cancer
As it has already been mentioned majority of bone cancers affect legs and arms. Primary bone cancers are known as sarcoma. There are several types of sarcoma. They are classified according to tissue and cells they are made of. The most common types of sarcomas are chondrosarcoma, Ewing's sarcoma and osteosarcoma.
Chrondrosarcoma predominantly affects adults and represents a malignant tumor made of cartilage. This tumor accounts for approximately 25% of all bone cancers. It is further classified based on how fast it grows and its likelihood to metastasis in 4 grades. Chondrosarcoma usually grows in the pelvic bone and shoulder bones as well as the superior metaphyseal and diaphyseal portions of the arms and legs.
Osteosarcoma is the most frequent type of bone cancer. It generally occurs in younger people (between the age of 10 and 25) and predominantly affects men. The tumor starts growing at the ends of bones mostly on long bones of the legs and arms.
Ewing's sarcoma is a rare bone tumor. It usually starts in the pelvis, femur, humerus, ribs and clavicle. Ewing's sarcoma is common among teenagers and even though it is classified as a bone tumor it is essential to mention that it possesses characteristics of both mesodermal and ectodermal origin which makes the tumor hard to classify.
Symptoms of Bone Cancer
Symptoms and signs of bone cancer depend on several factors and the size of the tumor as well as its locations are only two of them. The most prominent symptom of all bone cancers is pain. The pain may be initially occasional and mild in intensity while further growth of the tumor leads to chronic and more intensive pain. Apart from pain patients may develop additional symptoms and signs such as weight loss, night sweats, chills and fever.
Excessive growth of the tumor always leads to swelling of the affected bone and there may by a hard lump tender to touch above the level of the skin. The growth of the tumor makes the affected bone weak and it can easily break. The bone becomes extremely fragile and this is why many patients end up with pathological fractures.