What is sarcoma?
Sarcoma is a malignant tumor arising in connective tissue such as bone, muscle, tendons, fat or cartilage.
In order to determine the sarcoma type you have, microscopic investigation of tumor tissue is necessary. Apart from medical imaging (scans) doctors need to take a sample of the tumor you have, a biopsy.
Connective tissue is the body’s supporting tissue with several functions: protecting vital organs, reinforcement of the body (bones), shock absorber in joints (cartilage), heat preservation (fatty tissue) and movement (muscles and tendons). Blood vessels and nerves also partly consist of connective tissue.
Bone sarcoma arises in the bone, not in the bone marrow as in for example a myeloma. Metastases in the bone of other cancers such as breast cancer or prostate cancer are also not real bone cancer.
There are three types of bone sarcoma: osteosarcoma, Ewing sarcoma or chondrosarcoma.
Soft tissue sarcoma
Soft tissue sarcoma arises in the soft tissues of the supporting tissues such as muscles, fatty tissue, nervi tissue or tendons. There are about 70 different types of soft tissue sarcoma, each having their own characteristics.
Which parts of the body and who does sarcoma affect?
Sarcoma can literally arise in every part of the body and at every age. Bone sarcoma is most often found in adolescents in the knee region. Soft tissue sarcoma is most often found in the thigh.
What is the cause of sarcoma?
Sarcoma arises after certain cells go through an incorrect cell division (video) , and therefore keep on growing and dividing. Previous irradiation or lymphedema can trigger a higher risk for developing erroneous cell divisions in the affected region. Sometimes exposition to certain chemicals can also lead to a higher risk.
However, mostly no true cause can be found. There are no actions you have done wrong to provoke sarcoma, and there are no things you can do to avoid sarcoma. Do not blame yourself, getting sarcoma is just bad luck.
Which types of bone sarcoma are there?
There are three bone sarcoma types: osteosarcoma, Ewing sarcoma and chondrosarcoma. Below you can find information on each type.
Osteosarcoma is a malignant tumor arising in bone. Exceptionally, osteosarcoma can arise in soft tissues. An osteosarcoma produces immature bone that later ossifies. Usually it is found in adolescents and around the age of 60. The tumors most frequently affect the bones around the knee or the shoulder, but can also arise in other body regions. If no metastatic lesions are present at the time of diagnosis, the 5-year survival is about 65%.
Ewing sarcoma arises in bone and consists of many small blue cells. Usually the tumor affects children, adolescents and young adults. Ewing sarcoma can arise in any bone.
If no metastatic lesions are present at the time is diagnosis, the 5-year survival is about 75%.
Chondrosarcoma is a cartilage tumor arising inside the bone, or, less frequently, outside the bone.
In some patients a chondrosarcoma arises at the surface of a pre-existing bony growth, especially if they carry a hereditary genetic aberration.
Which soft tissue sarcoma type are there?
There are about 70 different types of soft tissue sarcoma. These sarcomas can arise in different tissues: muscles (rhabdomyosarcoma or leiomyosarcoma), blood vessels (angiosarcoma, hemangiopericytoma), nerves (malignant peripheral nerve sheath tumor),tendons, connective tissue (fibrosarcoma), fat (liposarcoma), and so on. The pathologist will determine from which tissue the sarcoma arises, and will perform additional (genetic) tests to further determine the tumor type. Sometimes the tumor is unlike any tissue,and thus is called a pleiomorphic sarcoma or NOS (not otherwise specified).
Soft tissue sarcomas can occur in three malignancy grades. Grade 1 or low grade means that these tumor types will rarely metastasise, but may easily recur at the original localisation.Grade 2 or intermediate grade will metastase more frequently, and are usually treated as high grade tumors.Grade 3 or high grade malignant means that these tumors will metastasise in about 50% of patients, usually towards the lungs.The risk of local recurrence is also much higher if the treatment is not sufficiently aggressive.