Primary Osteogenic Sarcoma with Pulmonary Metastasis: Clinical Results and Prognostic Factors in 91 Patients

Osteosarcoma is the most common primary malignant bone tumor. The long-term outcome is poor for patients with metastatic disease. From June 1989 to January 2008, 202 patients (128 males and 74 females) with high-grade osteosarcoma of the extremities were treated at our institution. Patients were divided into three groups depending on the time of identification of pulmonary metastasis: group A, identified with primary tumor diagnosis; group B, during whole treatment course; and group C, after completion of treatment. Long-term survival was calculated and factors related to metastases were analyzed. Ninety-one patients developed pulmonary metastases; 21 in group A, 18 in group B and 52 in group C. The mean period from initial diagnosis to lung metastases in groups B and C was 22.2 months (+/- 20.6). Five-year survival rates were 82.0% and 38.3% in the non-metastasis group and metastasis group, respectively (P < 0.001). The 5-year survival rate was significantly worse in group A than in group B or C (0%, 7.4%, 59.5%, P < 0.001), in patient with more than one lobe involved (27.0%, P = 0.006) and more than three pulmonary nodule metastases (21.3%, P = 0.002). Factors related to the pulmonary metastasis were: old age (65.5% in older than 27.5 years old and 41.6% in younger, P = 0.017), large tumor volume (54.4% in larger than 202.5 ml and 33.7% in smaller, P = 0.005) and elevated lactodehydrogenase (LDH; 55.1% vs.31.0% in normal, P = 0.001). The prognosis of osteosarcoma with pulmonary metastases is dismal, especially for patients who have primary pulmonary metastases, more than three pulmonary metastatic nodules or involvement of more than one lobe. Factors such as older age, larger tumor volume and elevated LDH may reflect high metastatic rate.