Before the use of chemotherapy (which began in the 1970s), osteosarcoma was treated primarily with surgical resection (usually amputation). Despite such good local control, more than 80% of patients subsequently developed recurrent disease that typically presented as pulmonary metastases. The high recurrence rate indicates that most patients have micrometastatic disease at the time of diagnosis. Therefore, the use of adjuvant (postoperative) systemic chemotherapy is critical for the treatment of patients with osteosarcoma.
The orthopedic surgeon is of paramount importance in the care of patients with osteosarcoma. Often, patients thought to have osteosarcoma are referred to the orthopedic surgeon first to make the diagnosis. Moreover, because osteosarcomas are not particularly responsive to radiotherapy, surgery is the only option for definitive tumor removal (local control).
In addition, an oncologic type of total joint prosthesis or complex bone reconstruction may be required following surgical resection. Therefore, close involvement of the orthopedic surgeon with the medical oncologist at the time of diagnosis, as well as during and after chemotherapy, is critical
The two main procedures performed by orthopedic surgeons in patients with osteosarcoma are biopsy and wide resection. Neither of these procedures should be undertaken unless complete tumor staging has been completed preoperatively. Such staging would typically include (but would not be limited to) the following (see Imaging Studies):
Plain radiography of the involved bone, including the joint above and the joint below the affected region
Total-body bone scanning
Magnetic resonance imaging (MRI) of the primary tumor area to include the entire bone of origin
Computed tomography (CT) of the lungs
Because osteosarcoma is a deadly form of cancer, no absolute contraindications to treatment exist. Relative contraindications would include situations in which the patient is so frail that the risks of general anesthesia outweigh any potential benefits of surgery. Another relative contraindication would be a situation in which the patient has extensive, overwhelming metastatic disease, and the benefits of comfort or hospice care outweigh the potential benefits of surgical intervention.
The genetic roots of cancer are irrefutable, and gene-focused basic science research holds tremendous promise for risk stratification, as well as for effective and innovative treatments. Multidrug-resistant varieties of osteosarcoma are a case in point. These cell lines have been shown to be genetically encoded with a certain membrane-bound glycoprotein that helps render these cancer cells "immune" to many chemotherapeutic agents. Early identification of such patients (perhaps at initial biopsy) would allow a tailored approach to neoadjuvant chemotherapy.
Metastatic or locally recurrent osteosarcoma presents an especially tough treatment challenge that remains incompletely answered. Patients in such cases find themselves in a particularly poor survival bracket. Future efforts must be aimed at improving chemotherapeutic and surgical treatments that can be offered to these patients.
One potential example of this is the bone-seeking radioisotope samarium (153-samarium ethylene diamine tetramethylene phosphonate), which has the potential to selectively deliver high doses of radiation to osteosarcoma cells. The safety and efficacy of this agent are being studied in patients with metastatic and locally recurrent osteosarcoma.