الفهرس | Only 14 pages are availabe for public view |
Abstract Chondrosarcoma is a malignant cancer whose tumor cells produce a pure hyaline cartilage that results in abnormal bone and/or cartilage growth. People who have chondrosarcoma have a tumor growth, or abnormal bony type of bump, which can vary in size and location. The term chondrosarcoma is used to define a heterogeneous group of lesions with diverse morphologic features and clinical behavior. Primary chondrosarcoma (or conventional chondrosarcoma) usually develops centrally in a previously normal bone. Secondary chondrosarcoma is a chondrosarcoma arising from a benign precursor such as enchondromas or osteochondromas. Chondrosarcoma is the third most common primary bone cancer. There are several different types of chondrosarcoma, with names based on the type of cells identified when they are examined under a microscope. Chrondrosarcoma can be histologically graded from 1 to 3 on the basis of the mitotic rate, cellularity, and nuclear size. Chondrosarcoma of bone generally has a good prognosis when optimally diagnosed and treated by an experienced team of specialists. Experienced assessment of histological grade and adequate histopathological and radiological (conventional x-ray, MRI, and in some cases CT) classification is used to guide treatment decisions. For conventional low-grade chondrosarcoma confined to the bone, intralesional curettage with local adjuvant therapy (phenol application or cryosurgery) is an option to decrease surgical morbidity. In intermediate- to high-grade tumors, clear margins are necessary to prevent recurrence. It is obvious that recurrences should be avoided, and when they occur they should be treated adequately, especially because they might be of higher histological grade, increasing the risk for metastases and a fatal outcome. Chondrosarcomas are relatively RT resistant; therefore, doses >60 Gy are needed for maximal local control after incomplete resection. Because this high-dose RT is often not feasible with conventional photons, new techniques, such as the use of protons or charged particles, have been tested, with promising results. |