Pulmonary resection of metastatic sarcoma: Prognostic factors associated with improved outcomes

Background: There are few data to predict the benefit of pulmonary metastasectomy in patients with extrathoracic sarcoma. This study analyzes prognostic factors associated with improved outcomes. Methods: Between June 2002 and December 2008, 97 patients underwent pulmonary resection for metastatic sarcoma at Massachusetts General Hospital. Eight patients were excluded because of lack of follow-up data. Analysis was performed using Kaplan-Meier estimates of survival, log-rank test, and multivariate Cox model. Results: Overall 5-year survival for the cohort was 50.1%. Patients who had multiple operations for recurrent pulmonary metastases had better 5-year survival compared with patients who had a single operation (69 versus 41%; p = 0.017). Median disease- free survival (DFS) for the reoperation group was 12.9 months compared with 9.1 months for the single-operation group (p < 0.028). Patients with a disease-free interval (DFI) greater than 12 months from detection of primary sarcoma to pulmonary metastasectomy had improved survival compared with those whose DFI was less than 12 months (p < 0.0001). Patients with bilateral metastasectomy had lower 5-year survival compared with metastasectomy for unilateral disease (22% versus 68%;p < 0.0001). Two or more metastases were associated with poorer outcome compared with a single metastasis (p = 0.0007). A positive resection margin portended worse survival compared with a negative resection margin (p = 0.004). Patients with lesions larger than 3 cm had decreased survival compared with patients with lesions smaller than 3 cm (p = 0.017) with no difference in median DFS. Histologic type, grade of tumor, and use of chemotherapy had no effect on survival. Multivariate analysis showed that patients with a DFI greater than 12 months (p = 0.001), single-sided metastasis (p = 0.001), negative margins (p = 0.002), and multiple operations (p = 0.018) had better survival. Conclusions: Pulmonary metastasectomy for sarcoma can be associated with prolonged survival. Tumor resectability, DFI, number of metastases, and laterality are important factors in determining patient selection for curative surgical intervention. Repeated pulmonary metastasectomy in select patients may improve survival despite recurrent disease.