Osteosarcoma and Malignant Fibrous Histiocytoma of Bone Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Osteosarcoma and MFH of Bone With Metastatic Disease at Diagnosis
Approximately 20% to 25% of patients with osteosarcoma present with clinically detectable metastatic disease. For patients with metastatic disease at initial presentation, roughly 20% will remain continuously free of disease, and roughly 30% will survive 5 years from diagnosis.
The lung is the most common site of initial metastatic disease. Patients with metastases limited to the lungs have a better outcome than patients with metastases to other sites or to the lungs combined with other sites.[1,3]
The chemotherapeutic agents used include high-dose methotrexate, doxorubicin, cisplatin, high-dose ifosfamide, etoposide, and in some reports, carboplatin or cyclophosphamide. High-dose ifosfamide (17.5 grams per course) in combination with etoposide produced a complete (10%) or partial (49%) response in patients with newly diagnosed metastatic osteosarcoma. The addition of either muramyl tripeptide or ifosfamide to a standard chemotherapy regimen that included cisplatin, high-dose methotrexate, and doxorubicin was evaluated using a factorial design in patients with metastatic osteosarcoma (n = 91). There was a nominal advantage for the addition of muramyl tripeptide (but not for ifosfamide) in terms of event-free survival (EFS) and overall survival (OS), but criteria for statistical significance were not met.
The treatment for malignant fibrous histiocytoma (MFH) of bone with metastasis at initial presentation is the same as the treatment for osteosarcoma with metastasis. Patients with unresectable or metastatic MFH have a very poor outcome.
Lung Metastases Only
Patients with metastatic lung lesions as the sole site of metastatic disease should have the lung lesions resected if at all possible. Generally, this is done following administration of preoperative chemotherapy. In approximately 10% of patients, all lung lesions disappear following preoperative chemotherapy. Complete resection of pulmonary metastatic disease can be achieved in a high percentage of patients with residual lung nodules following preoperative chemotherapy. The cure rate is essentially zero without complete resection of residual pulmonary metastatic lesions.
For patients who present with primary osteosarcoma and metastases limited to the lungs and who achieve complete surgical remission, 5-year EFS is approximately 20% to 25%. Multiple metastatic nodules confer a worse prognosis than one or two nodules, and bilateral lung involvement is worse than unilateral. Patients with peripheral lesions may have a better prognosis than those with central lesions. Patients with fewer than three nodules confined to one lung may achieve a 5-year EFS of approximately 40% to 50%.
Bone Only or Bone With Lung Metastasis
The second most common site of metastasis is another bone that is distant from the primary tumor. Patients with metastasis to other bones distant from the primary tumor experience roughly 10% EFS and OS. In the Italian experience, of the patients who presented with primary extremity tumors and synchronous metastasis to other bones, only 3 of 46 patients remained continuously disease-free 5 years later. Patients who have transarticular skip lesions have a poor prognosis.