Patients who develop metastatic disease from soft tissue sarcoma have a poor prognosis. The purpose of this study was to identify metastatic survival rates and identify prognostic variables that predict for these outcomes.
Between 2000 and 2010, 182 patients with stage I to IV primary soft tissue sarcomas of the extremity and trunk were treated with multimodality treatment. Fifty-five patients developed or presented with metastasis. We retrospectively analyzed prognostic factors for metastatic survival. Metastatic survival between groups was compared with the log-rank test. Survival curves were estimated by Kaplan-Meier plots. Multivariate analysis was performed using the Cox proportional hazards model.
Median follow-up was 3.1 years. Median metastatic survival was 24.2 months. Median metastatic survival in those undergoing multimodality therapies was 40 versus 22 months in those receiving single modality treatments. In single predictor Cox models, age, stage, number of lung metastases, location of metastases, and primary disease were significant for metastatic survival. On multivariate analysis, number of pulmonary metastases, histology, stage, and location of primary disease predicted for metastatic survival. Patients who had pulmonary-only disease had improved metastatic survival versus those that had extrapulmonary with or without pulmonary metastatic disease (38 vs. 15 mo). Patients who had ≤5 pulmonary metastasis had improved metastatic survival versus those that had >5 pulmonary lesions (55 vs. 22 mo).
This analysis shows that >5 pulmonary metastasis, malignant fibrous histiocytoma histology, stage III disease, and proximal lower extremity sarcomas are associated with decreased metastatic survival. Moreover, aggressive multimodality management of metastatic disease may prolong metastatic survival.